Method for monitoring physical downlink control channel, and device using same

ABSTRACT

Provided are a monitoring method/device for monitoring a downlink control channel of a terminal in a wireless communication system, and a downlink control channel transmission method/device corresponding to the monitoring method/device. A PS-PDCCH including power saving information is monitored in a DRX-on period, and when the PS-PDCCH is detected, a PDCCH is monitored on the basis of same. The PS-PDCCH may provide notification about a specific search space set among a plurality of search space sets, and exceptionally skip PDCCH monitoring for the specific search space set.

BACKGROUND OF THE DISCLOSURE Field of the Disclosure

The present disclosure relates to a method of monitoring a physicaldownlink control channel in a wireless communication system, and anapparatus using the method.

Related Art

As more and more communication devices require more communicationcapacity, there is a need for improved mobile broadband communicationover existing radio access technology. Also, massive machine typecommunications (MTC), which provides various services by connecting manydevices and objects, is one of the major issues to be considered in thenext generation communication. In addition, communication system designconsidering reliability/latency sensitive service/UE is being discussed.The introduction of next generation radio access technology consideringenhanced mobile broadband communication (eMBB), massive MTC (mMTC),ultra-reliable and low latency communication (URLLC) is discussed. Thisnew technology may be called new radio access technology (new RAT or NR)in the present disclosure for convenience. NR is also called the fifthgeneration (5G) system.

The improvement in performance and functions of a user equipment (UE)such as an increase in UE's display resolution, display size,processors, memories, and applications results in an increase in powerconsumption. It is important for the UE to reduce power consumptionsince power supply may be limited to a battery. This is also applied toa UE operating in NR.

One example for reducing power consumption of the UE includes adiscontinuous reception (DRX) operation. The UE may need to monitor aphysical downlink control channel (PDCCH) in every subframe to knowwhether there is data to be received. Since the UE does not alwaysreceive data in all subframes, such an operation results in unnecessarysignificant battery consumption. DRX is an operation for reducing thebattery consumption. That is, the UE wakes up with a period of a DRXcycle to monitor a PDCCH during a determined time (DRX on duration). Ifthere is no PDCCH detection during the time, the UE enters a sleepingmode, i.e., a state in which a radio frequency (RF) transceiver isturned off. In the presence of the PDCCH detection during the time, aPDCCH monitoring time may be extended, and data transmission andreception may be performed based on the detected PDCCH.

An additional method of reducing power consumption may also be requiredfor the DRX operation.

SUMMARY OF THE DISCLOSURE

The present disclosure provides a method of monitoring a physicaldownlink control channel in a wireless communication system, and anapparatus using the method.

In one aspect, provided is a method for monitoring a physical downlinkcontrol channel (PDCCH) of a user equipment (UE) in a wirelesscommunication system. The method includes monitoring a PS-PDCCHinforming power saving (PS) information in a discontinuous reception-on(DRX-on) duration and performing PDCCH monitoring in the DRX-on durationbased on the detected PS-PDCCH. The PS-PDCCH includes information for aspecific search space set among a plurality of search space setsconfigured for the DRX-on duration, and the PDCCH is monitored in searchspaces other than the specific search space set among the plurality ofsearch space sets.

In another aspect, provided is a user equipment (UE). The UE includes atransceiver transmitting and receiving a radio signal and a processoroperatively coupled with the transceiver. The processor monitors aPS-PDCCH informing power saving (PS) information in a discontinuousreception-on (DRX-on) duration, and performs PDCCH monitoring in theDRX-on duration based on the detected PS-PDCCH. The PS-PDCCH includesinformation for a specific search space set among a plurality of searchspace sets configured for the DRX-on duration, and the PDCCH ismonitored in search spaces other than the specific search space setamong the plurality of search space sets.

In still another aspect, provided is a method for transmitting aphysical downlink control channel (PDCCH) by a base station (BS) in awireless communication system. The method includes transmitting aPS-PDCCH informing power saving (PS) information in a discontinuousreception-on (DRX-on) duration and transmitting a PDCCH in the DRX-onduration based on the PS-PDCCH. The PS-PDCCH includes information for aspecific search space set among a plurality of search space setsconfigured for the DRX-on duration, and the PDCCH is transmitted insearch spaces other than the specific search space set among theplurality of search space sets.

In still another aspect, provided is a base station (BS). The BSincludes a transceiver transmitting and receiving a radio signal and aprocessor operatively coupled with the transceiver. The processortransmits a PS-PDCCH informing power saving (PS) information in adiscontinuous reception-on (DRX-on) duration, and transmits a PDCCH inthe DRX-on duration based on the PS-PDCCH. The PS-PDCCH includesinformation for a specific search space set among a plurality of searchspace sets configured for the DRX-on duration, and the PDCCH istransmitted in search spaces other than the specific search space setamong the plurality of search space sets.

In still another aspect, provided is an apparatus of a wirelesscommunication system. The apparatus includes a processor and a memoryoperatively coupled with the processor. The processor monitors aPS-PDCCH informing power saving (PS) information in a discontinuousreception-on (DRX-on) duration, and performs PDCCH monitoring in theDRX-on duration based on the detected PS-PDCCH. The PS-PDCCH includesinformation for a specific search space set among a plurality of searchspace sets configured for the DRX-on duration, and the PDCCH ismonitored in search spaces other than the specific search space setamong the plurality of search space sets.

In still another aspect, provided is at least one computer readablemedium (CRM). The CRM having instructions to be executed by at least oneprocessor, causing an apparatus to perform operations comprising:monitoring a PS-PDCCH informing power saving (PS) information in adiscontinuous reception-on (DRX-on) duration and performing PDCCHmonitoring in the DRX-on duration based on the detected PS-PDCCH. ThePS-PDCCH includes information for a specific search space set among aplurality of search space sets configured for the DRX-on duration, andthe PDCCH is monitored in search spaces other than the specific searchspace set among the plurality of search space sets.

Power consumption can be reduced in monitoring of a downlink controlchannel. Effects that can be obtained through specific examples of thepresent specification are not limited to the effects listed above. Forexample, there may be various technical effects that can be understoodor derived from the present specification by a person having ordinaryskill in the related art. Accordingly, specific effects of the presentspecification are not limited to those explicitly described herein, andmay include various effects that can be understood or derived from thetechnical features of the present specification.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a wireless communication system to which the presentdisclosure may be applied.

FIG. 2 is a diagram showing a wireless protocol architecture for a userplane.

FIG. 3 is a diagram showing a wireless protocol architecture for acontrol plane.

FIG. 4 illustrates a system structure of a next generation radio accessnetwork (NG-RAN) to which NR is applied.

FIG. 5 illustrates a functional division between an NG-RAN and a 5GC.

FIG. 6 illustrates an example of a frame structure that may be appliedin NR.

FIG. 7 illustrates a slot structure of an NR frame.

FIG. 8 illustrates CORESET.

FIG. 9 is a diagram illustrating a difference between a related artcontrol region and the CORESET in NR.

FIG. 10 illustrates an example of a frame structure for new radio accesstechnology.

FIG. 11 illustrates a structure of a self-contained slot.

FIG. 12 illustrates physical channels and typical signal transmission.

FIG. 13 illustrates a scenario in which three different bandwidth partsare configured.

FIG. 14 illustrates a DRX cycle.

FIG. 15 exemplifies reception of a PS-PDCCH used for GTS and anoperation of a UE according thereto.

FIG. 16 illustrates a method for monitoring a physical downlink controlchannel (PDCCH) of a UE.

FIG. 17 illustrates an operation between a network and a UE according tothe option 1.

FIG. 18 illustrates a wireless device applicable to the presentspecification.

FIG. 19 shows an example of a structure of a signal processing module.

FIG. 20 shows another example of a structure of a signal processingmodule in a transmitting device.

FIG. 21 illustrates an example of a wireless communication device forimplementing the present disclosure.

FIG. 22 shows an example of a processor 2000.

FIG. 23 shows an example of a processor 3000.

FIG. 24 shows another example of a wireless device.

FIG. 25 shows another example of a wireless device applied to thepresent specification.

FIG. 26 illustrates a hand-held device applied to the presentspecification.

FIG. 27 illustrates a communication system 1 applied to the presentspecification.

FIG. 28 illustrates a vehicle or an autonomous vehicle applicable to thepresent specification.

DESCRIPTION OF EXEMPLARY EMBODIMENTS

In the present specification, “A or B” may mean “only A”, “only B” or“both A and B”. In other words, in the present specification, “A or B”may be interpreted as “A and/or B”. For example, in the presentspecification, “A, B, or C” may mean “only A”, “only B”, “only C”, or“any combination of A, B, C”.

A slash (/) or comma used in the present specification may mean“and/or”. For example, “A/B” may mean “A and/or B”. Accordingly, “A/B”may mean “only A”, “only B”, or “both A and B”. For example, “A, B, C”may mean “A, B, or C”.

In the present specification, “at least one of A and B” may mean “onlyA”, “only B”, or “both A and B”. In addition, in the presentspecification, the expression “at least one of A or B” or “at least oneof A and/or B” may be interpreted as “at least one of A and B”.

In addition, in the present specification, “at least one of A, B, and C”may mean “only A”, “only B”, “only C”, or “any combination of A, B, andC”. In addition, “at least one of A, B, or C” or “at least one of A, B,and/or C” may mean “at least one of A, B, and C”.

In addition, a parenthesis used in the present specification may mean“for example”. Specifically, when indicated as “control information(PDCCH)”, it may mean that “PDCCH” is proposed as an example of the“control information”. In other words, the “control information” of thepresent specification is not limited to “PDCCH”, and “PDDCH” may beproposed as an example of the “control information”. In addition, whenindicated as “control information (i.e., PDCCH)”, it may also mean that“PDCCH” is proposed as an example of the “control information”.

Technical features described individually in one figure in the presentspecification may be individually implemented, or may be simultaneouslyimplemented.

FIG. 1 shows a wireless communication system to which the presentdisclosure may be applied. The wireless communication system may bereferred to as an Evolved-UMTS Terrestrial Radio Access Network(E-UTRAN) or a Long Term Evolution (LTE)/LTE-A system.

The E-UTRAN includes at least one base station (BS) 20 which provides acontrol plane and a user plane to a user equipment (UE) 10. The UE 10may be fixed or mobile, and may be referred to as another terminology,such as a mobile station (MS), a user terminal (UT), a subscriberstation (SS), a mobile terminal (MT), a wireless device, etc. The BS 20is generally a fixed station that communicates with the UE 10 and may bereferred to as another terminology, such as an evolved node-B (eNB), abase transceiver system (BTS), an access point, etc.

The BSs 20 are interconnected by means of an X2 interface. The BSs 20are also connected by means of an S1 interface to an evolved packet core(EPC) 30, more specifically, to a mobility management entity (MME)through S1-MME and to a serving gateway (S-GW) through S1-U.

The EPC 30 includes an MME, an S-GW, and a packet data network-gateway(P-GW). The MME has access information of the UE or capabilityinformation of the UE, and such information is generally used formobility management of the UE. The S-GW is a gateway having an E-UTRANas an end point. The P-GW is a gateway having a PDN as an end point.

Layers of a radio interface protocol between the UE and the network canbe classified into a first layer (L1), a second layer (L2), and a thirdlayer (L3) based on the lower three layers of the open systeminterconnection (OSI) model that is well-known in the communicationsystem. Among them, a physical (PHY) layer belonging to the first layerprovides an information transfer service by using a physical channel,and a radio resource control (RRC) layer belonging to the third layerserves to control a radio resource between the UE and the network. Forthis, the RRC layer exchanges an RRC message between the UE and the BS.

FIG. 2 is a diagram showing a wireless protocol architecture for a userplane. FIG. 3 is a diagram showing a wireless protocol architecture fora control plane. The user plane is a protocol stack for user datatransmission. The control plane is a protocol stack for control signaltransmission.

Referring to FIGS. 2 and 3, a PHY layer provides an upper layer(=higherlayer) with an information transfer service through a physical channel.The PHY layer is connected to a medium access control (MAC) layer whichis an upper layer of the PHY layer through a transport channel. Data istransferred between the MAC layer and the PHY layer through thetransport channel. The transport channel is classified according to howand with what characteristics data is transferred through a radiointerface.

Data is moved between different PHY layers, that is, the PHY layers of atransmitter and a receiver, through a physical channel. The physicalchannel may be modulated according to an Orthogonal Frequency DivisionMultiplexing (OFDM) scheme, and use the time and frequency as radioresources.

The functions of the MAC layer include mapping between a logical channeland a transport channel and multiplexing and demultiplexing to atransport block that is provided through a physical channel on thetransport channel of a MAC Service Data Unit (SDU) that belongs to alogical channel. The MAC layer provides service to a Radio Link Control(RLC) layer through the logical channel.

The functions of the RLC layer include the concatenation, segmentation,and reassembly of an RLC SDU. In order to guarantee various types ofQuality of Service (QoS) required by a Radio Bearer (RB), the RLC layerprovides three types of operation mode: Transparent Mode (TM),Unacknowledged Mode (UM), and Acknowledged Mode (AM). AM RLC provideserror correction through an Automatic Repeat Request (ARQ).

The RRC layer is defined only on the control plane. The RRC layer isrelated to the configuration, reconfiguration, and release of radiobearers, and is responsible for control of logical channels, transportchannels, and PHY channels. An RB means a logical route that is providedby the first layer (PHY layer) and the second layers (MAC layer, the RLClayer, and the PDCP layer) in order to transfer data between UE and anetwork.

The function of a Packet Data Convergence Protocol (PDCP) layer on theuser plane includes the transfer of user data and header compression andciphering. The function of the PDCP layer on the user plane furtherincludes the transfer and encryption/integrity protection of controlplane data.

What an RB is configured means a process of defining the characteristicsof a wireless protocol layer and channels in order to provide specificservice and configuring each detailed parameter and operating method. AnRB can be divided into two types of a Signaling RB (SRB) and a Data RB(DRB). The SRB is used as a passage through which an RRC message istransmitted on the control plane, and the DRB is used as a passagethrough which user data is transmitted on the user plane.

If RRC connection is established between the RRC layer of UE and the RRClayer of an E-UTRAN, the UE is in the RRC connected state. If not, theUE is in the RRC idle state.

A downlink transport channel through which data is transmitted from anetwork to UE includes a broadcast channel (BCH) through which systeminformation is transmitted and a downlink shared channel (SCH) throughwhich user traffic or control messages are transmitted. Traffic or acontrol message for downlink multicast or broadcast service may betransmitted through the downlink SCH, or may be transmitted through anadditional downlink multicast channel (MCH). Meanwhile, an uplinktransport channel through which data is transmitted from UE to a networkincludes a random access channel (RACH) through which an initial controlmessage is transmitted and an uplink shared channel (SCH) through whichuser traffic or control messages are transmitted.

Logical channels that are placed over the transport channel and that aremapped to the transport channel include a broadcast control channel(BCCH), a paging control channel (PCCH), a common control channel(CCCH), a multicast control channel (MCCH), and a multicast trafficchannel (MTCH).

The physical channel includes several OFDM symbols in the time domainand several subcarriers in the frequency domain. One subframe includes aplurality of OFDM symbols in the time domain. An RB is a resourcesallocation unit, and includes a plurality of OFDM symbols and aplurality of subcarriers. Furthermore, each subframe may use specificsubcarriers of specific OFDM symbols (e.g., the first OFDM symbol) ofthe corresponding subframe for a physical downlink control channel(PDCCH), that is, an L1/L2 control channel. A Transmission Time Interval(TTI) is a unit time for subframe transmission.

Hereinafter, a new radio access technology (new RAT, NR) will bedescribed.

As more and more communication devices require more communicationcapacity, there is a need for improved mobile broadband communicationover existing radio access technology. Also, massive machine typecommunications (MTC), which provides various services by connecting manydevices and objects, is one of the major issues to be considered in thenext generation communication. In addition, communication system designconsidering reliability/latency sensitive service/UE is being discussed.The introduction of next generation radio access technology consideringenhanced mobile broadband communication (eMBB), massive MTC (mMTC),ultrareliable and low latency communication (URLLC) is discussed. Thisnew technology may be called new radio access technology (new RAT or NR)in the present disclosure for convenience.

FIG. 4 illustrates a system structure of a next generation radio accessnetwork (NG-RAN) to which NR is applied.

Referring to FIG. 4, the NG-RAN may include a gNB and/or an eNB thatprovides user plane and control plane protocol termination to aterminal. FIG. 4 illustrates the case of including only gNBs. The gNBand the eNB are connected by an Xn interface. The gNB and the eNB areconnected to a 5G core network (5GC) via an NG interface. Morespecifically, the gNB and the eNB are connected to an access andmobility management function (AMF) via an NG-C interface and connectedto a user plane function (UPF) via an NG-U interface.

FIG. 5 illustrates a functional division between an NG-RAN and a 5GC.

Referring to FIG. 5, the gNB may provide functions such as an inter-cellradio resource management (Inter Cell RRM), radio bearer management (RBcontrol), connection mobility control, radio admission control,measurement configuration & provision, dynamic resource allocation, andthe like. The AMF may provide functions such as NAS security, idle statemobility handling, and so on. The UPF may provide functions such asmobility anchoring, PDU processing, and the like. The SMF may providefunctions such as UE IP address assignment, PDU session control, and soon.

FIG. 6 illustrates an example of a frame structure that may be appliedin NR.

Referring to FIG. 6, in the NR, a radio frame (hereinafter, alsoreferred to as a frame) may be used in uplink and downlinktransmissions. The frame has a length of 10 ms, and may be defined astwo 5 ms half-frames (HFs). The HF may be defined as five 1 ms subframes(SFs). The SF may be divided into one or more slots, and the number ofslots within the SF depends on a subcarrier spacing (SCS). Each slotincludes 12 or 14 OFDM(A) symbols according to a cyclic prefix (CP). Incase of using a normal CP, each slot includes 14 symbols. In case ofusing an extended CP, each slot includes 12 symbols. Herein, a symbolmay include an OFDM symbol (or CP-OFDM symbol) and a Single Carrier-FDMA(SC-FDMA) symbol (or Discrete Fourier Transform-spread-OFDM (DFT-s-OFDM)symbol).

The following table 1 illustrates a subcarrier spacing configuration μ.

TABLE 1 μ Δf =2^(μ)•15[kHz] Cyclic prefix 0 15 Normal 1 30 Normal 2 60Normal Extended 3 120 normal 4 240 normal

The following table 2 illustrates the number of slots in a frame(N^(frame,μ) _(slot)), the number of slots in a subframe (N^(subframe,μ)_(slot)), the number of symbols in a slot (N^(slot) _(symb)), and thelike, according to subcarrier spacing configurations μ.

TABLE 2 μ N^(slot) _(symb) N^(frame,μ) _(slot) N^(subframe,μ) _(slot) 014 10 1 1 14 20 2 2 14 40 4 3 14 80 8 4 14 160 16

FIG. 6 illustrates a case of μ=0, 1, 2, 3.

Table 2-1 below illustrates that the number of symbols per slot, thenumber of slots per frame, and the number of slots per subframe varydepending on the SCS, in case of using an extended CP.

TABLE 2-1 μ N^(slot) _(symb) N^(frame,μ) _(slot) N_(slot) ^(subframe,μ)2 12 40 4

In an NR system, OFDM(A) numerologies (e.g., SCS, CP length, and so on)may be differently configured between a plurality of cells integrated toone UE. Accordingly, an (absolute time) duration of a time resource(e.g., SF, slot or TTI) (for convenience, collectively referred to as atime unit (TU)) configured of the same number of symbols may bedifferently configured between the integrated cells.

FIG. 7 illustrates a slot structure of an NR frame.

A slot may include a plurality of symbols in a time domain. For example,in case of a normal CP, one slot may include 7 symbols. However, in caseof an extended CP, one slot may include 6 symbols. A carrier may includea plurality of subcarriers in a frequency domain. A resource block (RB)may be defined as a plurality of consecutive subcarriers (e.g., 12subcarriers) in the frequency domain. A bandwidth part (BWP) may bedefined as a plurality of consecutive (physical) resource blocks((P)RBs) in the frequency domain, and the BWP may correspond to onenumerology (e.g., SCS, CP length, and so on). The carrier may include upto N (e.g., 5) BWPs. Data communication may be performed via anactivated BWP, and only one BWP may be activated for one UE. In aresource grid, each element may be referred to as a resource element(RE), and one complex symbol may be mapped thereto.

A physical downlink control channel (PDCCH) may include one or morecontrol channel elements (CCEs) as illustrated in the following table 3.

TABLE 3 Aggregation level Number of CCEs 1 1 2 2 4 4 8 8 16 16

That is, the PDCCH may be transmitted through a resource including 1, 2,4, 8, or 16 CCEs. Here, the CCE includes six resource element groups(REGs), and one REG includes one resource block in a frequency domainand one orthogonal frequency division multiplexing (OFDM) symbol in atime domain.

Monitoring implies decoding of each PDCCH candidate according to adownlink control information (DCI) format. The UE monitors a set ofPDCCH candidates in one or more CORESETs (to be described below) on anactive DL BWP of each activated serving cell in which PDCCH monitoringis configured, according to a corresponding search space set.

A new unit called a control resource set (CORESET) may be introduced inthe NR. The UE may receive a PDCCH in the CORESET.

FIG. 8 illustrates CORESET.

Referring to FIG. 8, the CORESET includes N^(CORESET) _(RB) number ofresource blocks in the frequency domain, and N^(CORESET) _(symb)∈{1, 2,3} number of symbols in the time domain. N^(CORESET) _(RB) andN^(CORESET) _(symb) may be provided by a base station via higher layersignaling. As illustrated in FIG. 8, a plurality of CCEs (or REGs) maybe included in the CORESET.

The UE may attempt to detect a PDCCH in units of 1, 2, 4, 8, or 16 CCEsin the CORESET. One or a plurality of CCEs in which PDCCH detection maybe attempted may be referred to as PDCCH candidates.

A plurality of CORESETs may be configured for the terminal.

FIG. 9 is a diagram illustrating a difference between a related artcontrol region and the CORESET in NR.

Referring to FIG. 9, a control region 800 in the related art wirelesscommunication system (e.g., LTE/LTE-A) is configured over the entiresystem band used by a base station (BS). All the terminals, excludingsome (e.g., eMTC/NB-IoT terminal) supporting only a narrow band, must beable to receive wireless signals of the entire system band of the BS inorder to properly receive/decode control information transmitted by theBS.

On the other hand, in NR, CORESET described above was introduced.CORESETs 801, 802, and 803 are radio resources for control informationto be received by the terminal and may use only a portion, rather thanthe entirety of the system bandwidth. The BS may allocate the CORESET toeach UE and may transmit control information through the allocatedCORESET. For example, in FIG. 9, a first CORESET 801 may be allocated toUE 1, a second CORESET 802 may be allocated to UE 2, and a third CORESET803 may be allocated to UE 3. In the NR, the terminal may receivecontrol information from the BS, without necessarily receiving theentire system band.

The CORESET may include a UE-specific CORESET for transmittingUE-specific control information and a common CORESET for transmittingcontrol information common to all UEs.

Meanwhile, NR may require high reliability according to applications. Insuch a situation, a target block error rate (BLER) for downlink controlinformation (DCI) transmitted through a downlink control channel (e.g.,physical downlink control channel (PDCCH)) may remarkably decreasecompared to those of conventional technologies. As an example of amethod for satisfying requirement that requires high reliability,content included in DCI can be reduced and/or the amount of resourcesused for DCI transmission can be increased. Here, resources can includeat least one of resources in the time domain, resources in the frequencydomain, resources in the code domain and resources in the spatialdomain.

In NR, the following technologies/features can be applied.

<Self-Contained Subframe Structure>

FIG. 10 illustrates an example of a frame structure for new radio accesstechnology.

In NR, a structure in which a control channel and a data channel aretime-division-multiplexed within one TTI, as shown in FIG. 10, can beconsidered as a frame structure in order to minimize latency.

In FIG. 10, a shaded region represents a downlink control region and ablack region represents an uplink control region. The remaining regionmay be used for downlink (DL) data transmission or uplink (UL) datatransmission. This structure is characterized in that DL transmissionand UL transmission are sequentially performed within one subframe andthus DL data can be transmitted and UL ACK/NACK can be received withinthe subframe. Consequently, a time required from occurrence of a datatransmission error to data retransmission is reduced, thereby minimizinglatency in final data transmission.

In this data and control TDMed subframe structure, a time gap for a basestation and a terminal to switch from a transmission mode to a receptionmode or from the reception mode to the transmission mode may berequired. To this end, some OFDM symbols at a time when DL switches toUL may be set to a guard period (GP) in the self-contained subframestructure.

FIG. 11 illustrates a structure of a self-contained slot.

In an NR system, a DL control channel, DL or UL data, a UL controlchannel, and the like may be contained in one slot. For example, first Nsymbols (hereinafter, DL control region) in the slot may be used totransmit a DL control channel, and last M symbols (hereinafter, ULcontrol region) in the slot may be used to transmit a UL controlchannel. N and M are integers greater than or equal to 0. A resourceregion (hereinafter, a data region) which exists between the DL controlregion and the UL control region may be used for DL data transmission orUL data transmission. For example, the following configuration may beconsidered. Respective durations are listed in a temporal order.

1. DL only configuration

2. UL only configuration

3. Mixed UL-DL configuration

-   -   DL region+Guard period (GP)+UL control region    -   DL control region+GP+UL region

DL region: (i) DL data region, (ii) DL control region+DL data region

UL region: (i) UL data region, (ii) UL data region+UL control region

A PDCCH may be transmitted in the DL control region, and a physicaldownlink shared channel (PDSCH) may be transmitted in the DL dataregion. A physical uplink control channel (PUCCH) may be transmitted inthe UL control region, and a physical uplink shared channel (PUSCH) maybe transmitted in the UL data region. Downlink control information(DCI), for example, DL data scheduling information, UL data schedulinginformation, and the like, may be transmitted on the PDCCH. Uplinkcontrol information (UCI), for example, ACK/NACK information about DLdata, channel state information (CSI), and a scheduling request (SR),may be transmitted on the PUCCH. A GP provides a time gap in a processin which a BS and a UE switch from a TX mode to an RX mode or a processin which the BS and the UE switch from the RX mode to the TX mode. Somesymbols at the time of switching from DL to UL within a subframe may beconfigured as the GP.

<Analog Beamforming #1>

Wavelengths are shortened in millimeter wave (mmW) and thus a largenumber of antenna elements can be installed in the same area. That is,the wavelength is 1 cm at 30 GHz and thus a total of 100 antennaelements can be installed in the form of a 2-dimensional array at aninterval of 0.5 lambda (wavelength) in a panel of 5×5 cm. Accordingly,it is possible to increase a beamforming (BF) gain using a large numberof antenna elements to increase coverage or improve throughput in mmW.

In this case, if a transceiver unit (TXRU) is provided to adjusttransmission power and phase per antenna element, independentbeamforming per frequency resource can be performed. However,installation of TXRUs for all of about 100 antenna elements decreaseseffectiveness in terms of cost. Accordingly, a method of mapping a largenumber of antenna elements to one TXRU and controlling a beam directionusing an analog phase shifter is considered. Such analog beamforming canform only one beam direction in all bands and thus cannot providefrequency selective beamforming.

Hybrid beamforming (BF) having a number B of TXRUs which is smaller thanQ antenna elements can be considered as an intermediate form of digitalBF and analog BF. In this case, the number of directions of beams whichcan be simultaneously transmitted are limited to B although it dependson a method of connecting the B TXRUs and the Q antenna elements.

<Analog Beamforming #2>

When a plurality of antennas is used in NR, hybrid beamforming which isa combination of digital beamforming and analog beamforming is emerging.Here, in analog beamforming (or RF beamforming) an RF end performsprecoding (or combining) and thus it is possible to achieve theperformance similar to digital beamforming while reducing the number ofRF chains and the number of D/A (or A/D) converters. For convenience,the hybrid beamforming structure may be represented by N TXRUs and Mphysical antennas. Then, the digital beamforming for the L data layersto be transmitted at the transmitting end may be represented by an N byL matrix, and the converted N digital signals are converted into analogsignals via TXRUs, and analog beamforming represented by an M by Nmatrix is applied.

System information of the NR system may be transmitted in a broadcastingmanner. In this case, in one symbol, analog beams belonging to differentantenna panels may be simultaneously transmitted. A scheme ofintroducing a beam RS (BRS) which is a reference signal (RS) transmittedby applying a single analog beam (corresponding to a specific antennapanel) is under discussion to measure a channel per analog beam. The BRSmay be defined for a plurality of antenna ports, and each antenna portof the BRS may correspond to a single analog beam. In this case, unlikethe BRS, a synchronization signal or an xPBCH may be transmitted byapplying all analog beams within an analog beam group so as to becorrectly received by any UE.

In the NR, in a time domain, a synchronization signal block (SSB, oralso referred to as a synchronization signal and physical broadcastchannel (SS/PBCH)) may consist of 4 OFDM symbols indexed from 0 to 3 inan ascending order within a synchronization signal block, and a PBCHassociated with a primary synchronization signal (PSS), secondarysynchronization signal (SSS), and demodulation reference signal (DMRS)may be mapped to the symbols. As described above, the synchronizationsignal block may also be represented by an SS/PBCH block.

In NR, since a plurality of synchronization signal blocks(SSBs) may betransmitted at different times, respectively, and the SSB may be usedfor performing initial access (IA), serving cell measurement, and thelike, it is preferable to transmit the SSB first when transmission timeand resources of the SSB overlap with those of other signals. To thispurpose, the network may broadcast the transmission time and resourceinformation of the SSB or indicate them through UE-specific RRCsignaling.

In NR, beams may be used for transmission and reception. If receptionperformance of a current serving beam is degraded, a process ofsearching for a new beam through the so-called Beam Failure Recovery(BFR) may be performed.

Since the BFR process is not intended for declaring an error or failureof a link between the network and a UE, it may be assumed that aconnection to the current serving cell is retained even if the BFRprocess is performed. During the BFR process, measurement of differentbeams (which may be expressed in terms of CSI-RS port or SynchronizationSignal Block (SSB) index) configured by the network may be performed,and the best beam for the corresponding UE may be selected. The UE mayperform the BFR process in a way that it performs an RACH processassociated with a beam yielding a good measurement result.

Now, a transmission configuration indicator (hereinafter, TCI) statewill be described. The TCI state may be configured for each CORESET of acontrol channel, and may determine a parameter for determining an RXbeam of the UE, based on the TCI state.

For each DL BWP of a serving cell, a UE may be configured for three orfewer CORESETs. Also, a UE may receive the following information foreach CORESET.

1) CORESET index p (one of 0 to 11, where index of each CORESET may bedetermined uniquely among BWPs of one serving cell),

2) PDCCH DM-RS scrambling sequence initialization value,

3) Duration of a CORESET in the time domain (which may be given insymbol units),

4) Resource block set,

5) CCE-to-REG mapping parameter,

6) Antenna port quasi co-location indicating quasi co-location (QCL)information of a DM-RS antenna port for receiving a PDCCH in eachCORESET (from a set of antenna port quasi co-locations provided by ahigher layer parameter called ‘TCI-State’),

7) Indication of presence of Transmission Configuration Indication (TCI)field for a specific DCI format transmitted by the PDCCH in the CORESET,and so on.

QCL will be described. If a characteristic of a channel through which asymbol on one antenna port is conveyed can be inferred from acharacteristic of a channel through which a symbol on the other antennaport is conveyed, the two antenna ports are said to be quasi co-located(QCLed). For example, when two signals A and B are transmitted from thesame transmission antenna array to which the same/similar spatial filteris applied, the two signals may go through the same/similar channelstate. From a perspective of a receiver, upon receiving one of the twosignals, another signal may be detected by using a channelcharacteristic of the received signal.

In this sense, when it is said that the signals A and B are quasico-located (QCLed), it may mean that the signals A and B have wentthrough a similar channel condition, and thus channel informationestimated to detect the signal A is also useful to detect the signal B.Herein, the channel condition may be defined according to, for example,a Doppler shift, a Doppler spread, an average delay, a delay spread, aspatial reception parameter, or the like.

A ‘TCI-State’ parameter associates one or two downlink reference signalsto corresponding QCL types (QCL types A, B, C, and D, see Table 4).

TABLE 4 QCL Type Description QCL-TypeA Doppler shift, Doppler spread,Average delay, Delay spread QCL-TypeB Doppler shift, Doppler spread'QCL-TypeC Doppler shift, Average delay QCL-TypeD Spatial Rx parameter

Each ‘TCI-State’ may include a parameter for configuring a QCL relationbetween one or two downlink reference signals and a DM-RS port of aPDSCH (or PDDCH) or a CSI-RS port of a CSI-RS resource.

Meanwhile, for each DL BWP configured to a UE in one serving cell, theUE may be provided with 10 (or less) search space sets. For each searchspace set, the UE may be provided with at least one of the followinginformation.

1) search space set index s (0≤s<40), 2) an association between aCORESET p and the search space set s, 3) a PDCCH monitoring periodicityand a PDCCH monitoring offset (slot unit), 4) a PDCCH monitoring patternwithin a slot (e.g., indicating a first symbol of a CORSET in a slot forPDCCH monitoring), 5) the number of slots in which the search space sets exists, 6) the number of PDCCH candidates per CCE aggregation level,7) information indicating whether the search space set s is CSS or USS.

In the NR, a CORESET #0 may be configured by a PBCH (or a UE-dedicatedsignaling for handover or a PSCell configuration or a BWPconfiguration). A search space (SS) set #0 configured by the PBCH mayhave monitoring offsets (e.g., a slot offset, a symbol offset) differentfor each associated SSB. This may be required to minimize a search spaceoccasion to be monitored by the UE. Alternatively, this may be requiredto provide a beam sweeping control/data region capable of performingcontrol/data transmission based on each beam so that communication withthe UE is persistently performed in a situation where a best beam of theUE changes dynamically.

FIG. 12 illustrates physical channels and typical signal transmission.

Referring to FIG. 12, in a wireless communication system, a UE receivesinformation from a BS through a downlink (DL), and the UE transmitsinformation to the BS through an uplink (UL). The informationtransmitted/received by the BS and the UE includes data and a variety ofcontrol information, and there are various physical channels accordingto a type/purpose of the information transmitted/received by the BS andthe UE.

The UE which is powered on again in a power-off state or which newlyenters a cell performs an initial cell search operation such asadjusting synchronization with the BS or the like (S11). To this end,the UE receives a primary synchronization channel (PSCH) and a secondarysynchronization channel (SSCH) from the BS to adjust synchronizationwith the BS, and acquire information such as a cell identity (ID) or thelike. In addition, the UE may receive a physical broadcast channel(PBCH) from the BS to acquire broadcasting information in the cell. Inaddition, the UE may receive a downlink reference signal (DL RS) in aninitial cell search step to identify a downlink channel state.

Upon completing the initial cell search, the UE may receive a physicaldownlink control channel (PDCCH) and a physical downlink control channel(PDSCH) corresponding thereto to acquire more specific systeminformation (S12).

Thereafter, the UE may perform a random access procedure to complete anaccess to the BS (S13˜S16). Specifically, the UE may transmit a preamblethrough a physical random access channel (PRACH) (S13), and may receivea random access response (RAR) for the preamble through a PDCCH and aPDSCH corresponding thereto (S14). Thereafter, the UE may transmit aphysical uplink shared channel (PUSCH) by using scheduling informationin the RAR (S15), and may perform a contention resolution proceduresimilarly to the PDCCH and the PDSCH corresponding thereto (S16).

After performing the aforementioned procedure, the UE may performPDCCH/PDSCH reception (S17) and PUSCH/physical uplink control channel(PUCCH) transmission (S18) as a typical uplink/downlink signaltransmission procedure. Control information transmitted by the UE to theBS is referred to as uplink control information (UCI). The UCI includeshybrid automatic repeat and request (HARD) acknowledgement(ACK)/negative-ACK (HACK), scheduling request (SR), channel stateinformation (CSI), or the like. The CSI includes a channel qualityindicator (CQI), a precoding matrix indicator (PMI), a rank indication(RI), or the like. In general, the UCI is transmitted through the PUCCH.However, when control information and data are to be transmittedsimultaneously, the UCI may be transmitted through the PUSCH. Inaddition, the UE may aperiodically transmit the UCI through the PUSCHaccording to a request/instruction of a network.

In order to enable reasonable battery consumption when bandwidthadaptation (BA) is configured, only one uplink BWP and one downlink BWPor only one downlink/uplink BWP pair for each uplink carrier may beactivated at once in an active serving cell, and all other BWPsconfigured in the UE are deactivated. In the deactivated BWPs, the UEdoes not monitor the PDCCH, and does not perform transmission on thePUCCH, PRACH, and UL-SCH.

For the BA, RX and TX bandwidths of the UE are not necessarily as wideas a bandwidth of a cell, and may be adjusted. That is, it may becommanded such that a width is changed (e.g., reduced for a period oflow activity for power saving), a position in a frequency domain ismoved (e.g., to increase scheduling flexibility), and a subcarrierspacing is changed (e.g., to allow different services). A subset of theentire cell bandwidth of a cell is referred to as a bandwidth part(BWP), and the BA is acquired by configuring BWP(s) to the UE and bynotifying the UE about a currently active BWP among configured BWPs.When the BA is configured, the UE only needs to monitor the PDCCH on oneactive BWP. That is, there is no need to monitor the PDCCH on the entiredownlink frequency of the cell. A BWP inactive timer (independent of theaforementioned DRX inactive timer) is used to switch an active BWP to adefault BWP. That is, the timer restarts when PDCCH decoding issuccessful, and switching to the default BWP occurs when the timerexpires.

FIG. 13 illustrates a scenario in which three different bandwidth partsare configured.

FIG. 13 shows an example in which BWP₁, BWP₂, and BWP₃ are configured ona time-frequency resource. The BWP₁ may have a width of 40 MHz and asubcarrier spacing of 15 kHz. The BWP₂ may have a width of 10 MHz and asubcarrier spacing of 15 kHz. The BWP₃ may have a width of 20 MHz and asubcarrier spacing of 60 kHz. In other words, each BWP may have adifferent width and/or a different subcarrier spacing.

Now, discontinuous reception (DRX) will be described.

FIG. 14 illustrates a DRX cycle.

Referring to FIG. 14, the DRX cycle includes an ‘on duration(hereinafter, also referred to as a ‘DRX-on duration’) and an‘opportunity for DRX’. The DRX cycle defines a time interval in whichthe on-duration is cyclically repeated. The on-duration indicates a timeduration in which a UE performs monitoring to receive a PDCCH. If DRX isconfigured, the UE performs PDCCH monitoring during the ‘on-duration’.If there is a PDCCH successfully detected during the PDCCH monitoring,the UE operates an inactivity timer and maintains an awake state. On theother hand, if there is no PDCCH successfully detected during the PDCCHmonitoring, the UE enters a sleep state after the ‘on-duration’ ends.

Table 5 shows a UE procedure related to DRX (RRC_CONNECTED state).Referring to Table 5, DRX configuration information may be receivedthrough higher layer (e.g., RRC) signaling. Whether DRX is ON or OFF maybe controlled by a DRX command of a MAC layer. If the DRX is configured,PDCCH monitoring may be performed discontinuously.

TABLE 5 Type of signals UE procedure 1st step RRC signalling - ReceiveDRX configuration (MAC-CellGroupConfig) information 2nd step MAC CE -Receive DRX command ((Long) DRX command MAC CE) 3rd step — Monitor aPDCCH during an on- duration of a DRX cycle

MAC-CellGroupConfig may include configuration information required toconfigure a medium access control (MAC) parameter for a cell group.MAC-CellGroupConfig may also include configuration information regardingDRX. For example, MAC-CellGroupConfig may include information fordefining DRX as follows.

-   -   Value of drx-OnDurationTimer: This defines a length of a        starting duration of a DRX cycle. It may be a timer related to a        DRX-on duration.    -   Value of drx-InactivityTimer: This defines a length of a time        duration in which the UE is in an awake state, after a PDCCH        occasion in which a PDCCH indicating initial UL or DL data is        detected.    -   Value of drx-HARQ-RTT-TimerDL: This defines a length of a        maximum time duration until DL retransmission is received, after        DL initial transmission is received.    -   Value of drx-HARQ-RTT-TimerDL: This defines a length of a        maximum time duration until a grant for UL retransmission is        received, after a grant for UL initial transmission is received.    -   drx-LongCycleStartOffset: This defines a time length and a        starting point of a DRX cycle    -   drx-ShortCycle (optional): This defines a time length of a short        DRX cycle.

Herein, if any one of drx-OnDurationTimer, drx-InactivityTimer,drx-HARQ-RTT-TimerDL, and drx-HARQ-RTT-TimerDL is operating, the UEperforms PDCCH monitoring in every PDCCH occasion while maintaining anawake state.

The UE may know a starting point of a DRX cycle, a duration (durationtime) of the DRX cycle, a starting point of an on-duration timer, and aduration of the on-duration timer according to a DRX configuration.Thereafter, the UE attempts reception/detection for schedulinginformation (i.e., PDCCH) within the on-duration of each DRX cycle (thismay be represented that scheduling information is monitored).

If the scheduling information (PDCCH) is detected within the on-durationof the DRX cycle (DRX-on duration), an inactivity timer is activated,and detection is attempted for another scheduling information during agiven inactivity timer duration (a time duration in which the inactivitytimer runs). In this case, the on-duration and the inactivity timerduration in which the UE performs the signal reception/detectionoperation may be together referred to as an active time. If thescheduling information is not detected in the on-duration, only theon-duration may be the active time.

When the inactivity timer ends without reception/detection of anadditional signal (a control signal or data), the UE does not performscheduling information and corresponding DL reception/UL transmissionuntil an on-duration of a next DRX cycle (a DRX on duration) startsafter the inactivity timer ends.

A duration adjustment of a DRX cycle, a duration adjustment of anon-duration timer/inactivity timer, or the like plays an important rolein determining whether the UE sleeps. According to the setting for acorresponding parameter, the network may configure the UE to frequentlysleep or continuously perform monitoring on the scheduling information.This may act as an element for determining whether power saving of theUE will be achieved.

Now, the present disclosure will be described.

Hereinafter, a PDCCH which provides power saving (PS) information willbe referred to as a PS-PDCCH. That is, the PS-PDCCH may be a PDCCHnotifying of the PS information. Whether to apply a power saving scheme,a method of applying the power saving scheme, or the like may beindicated to the UE by using the PS-PDCCH.

For example, a DCI format notifying of the PS information through thePS-PDCCH (for convenience, such a DCI format is referred to as a DCIformat 2_6) may be received outside (other than) a DRX active time.Hereinafter, receiving the PS-PDCCH may have the equivalent meaning asreceiving the DCI format (e.g., DCI format 2_6) through the PS-PDCCH.

For example, the following information may be included in the DCI format(e.g., DCI format 2_6) notifying of the PS information.

1. Block numbers (block number 1, block number 2, . . . , block numberN): One block may be configured to a UE.

2. Wake-up indicator (1 bit): This indicates whether a UE wakes up.

3. Secondary cell (Scell) dormancy indication

A PS-PDCCH may be used for PDCCH monitoring adaptation which is one ofpower saving schemes. The PDCCH monitoring adaptation may imply a schemeof adaptively skipping PDCCH monitoring or reducing PDCCH monitoringaccording to conditions in PDCCH monitoring occasions (which may imply atime point at which the PDCCH can be monitored) in which PDCCHmonitoring is scheduled.

A PS-PDCCH for the purpose of PDCCH monitoring adaptation may be usedfor the purpose of search space set on/off. In this case, not onlyon/off for an individual search space set but also on/off for total(configured) search space sets is possible. Thus, wake-up andgo-to-sleep functions may be included.

<PS-PDCCH Monitoring for PDCCH Monitoring Adaptation>

A PS-PDCCH monitoring method or the like is proposed in terms of searchspace (hereinafter, SS) set configuration adaptation. In general,content proposed below may be applied not only to a PS-PDCCH for thepurpose of PDCCH monitoring adaptation (and/or SS set configurationadaptation) but also to PS-PDCCH reception related to power saving ofother purposes.

1. Monitoring Occasion Determination for PS-PDCCH

A monitoring occasion based on a typical SS set configuration may bedetermined by monitoring-related parameters (e.g., monitoringperiodicity, pattern, duration, offset, etc.) in the SS setconfiguration.

On the other hand, a monitoring occasion for a PS-PDCCH (e.g., PS-PDCCHfor the wake-up purpose) may be determined by the following method.Herein, the PS-PDCCH for the wake-up purpose may imply a part of aPS-PDCCH for the SS set configuration adaptation, or may imply aPS-PDCCH configured independent of the PS-PDCCH for the SS setconfiguration adaptation. In addition, a wake-up indication may betransmitted independently through one PS-PDCCH, or may be transmitted byusing some fields in one PS-PDCCH together with another power savingscheme.

Hereinafter, although the proposed content is described based on adiscontinuous reception (DRX) operation, the same method may also beapplied to the non-DRX operation in the present disclosure.

In addition, wake-up in the present disclosure may be applied to allconfigured SS sets or may indicate wake-up for a specific SS set. Forexample, when wake-up is indicated for all configured SS sets, a UE mayperform PDCCH monitoring in a PDCCH monitoring occasion specified forthe all SS sets, and when wake-up is indicated for a specific SS set,PDCCH monitoring may be performed in a PSCCH monitoring occasionspecified for the specific SS set.

The following option may be implemented alone or in combination. Inaddition, as described above, a PS-PDCCH indicating adaptation for an SSset configuration may operate as a PS-PDCCH for the wake-up orgo-to-sleep purpose. For example, among monitoring occasions of thePS-PDCCH performing adaptation for the SS set configuration, amonitoring occasion located temporally first in an on-duration of a DRXoperation may be interpreted for the wake-up purpose.

A monitoring occasion for a wake-up PS-PDCCH is proposed below, and amonitoring-related parameter may be configured in a PDCCH for powersaving other than wake-up by the existing SS set configuration or thelike.

If the PS-PDCCH for the wake-up purpose is a part of the PS-PDCCH for SSset configuration adaptation, the wake-up PS-PDCCH may imply a PS-PDCCHtransmitted in some monitoring occasions among monitoring occasions ofan SS set which monitors the SS set configuration adaptation PS-PDCCH.

Option 1) Offset Between PS-PDCCH Monitoring Occasion and On-Duration

A network may use a PS-PDCCH to indicate whether a UE will perform PDCCHmonitoring in a corresponding DRX cycle (for all SS set(s) or specificSS set(s)). In this case, a monitoring occasion of a (wake-up) PS-PDCCHmay be determined based on an offset with an on-duration (e.g., a DRX-onduration). For example, assuming that a monitoring occasion is locatedin a slot before (or after) a specific slot from a starting slot of anon-duration, the specific slot may be determined based on an offsetvalue. Specifically, the specific slot may be directly indicated by theoffset value, or the specific slot may be indirectly indicated such thatmonitoring is performed only in a monitoring occasion located in aspecific time duration which comes after a slot indicated by the offsetvalue. This will be described below in greater detail.

The offset value may be predefined, or may be indicated by the networkthrough higher layer signaling (e.g., RRC signaling) or the like.

The aforementioned option 1) may imply that a monitoring occasion for aPS-PDCCH (for the wake-up purpose) is configured independently, even ifa monitoring occasion is configured by an SS set configuration for aPS-PDCCH.

The monitoring occasion of the PS-PDCCH (for notifying of whetherwake-up is achieved) may be located in a plurality of slots consecutivefrom a monitoring occasion location designated by the aforementionedoffset (or designed by a specific period, e.g., 2 slots, 4 slots, etc.).This may be used to increase a detection probability of the wake-upPS-PDCCH. Increasing of the detection probability may imply that DCI ofthe same content is repeatedly transmitted in a state of assuming thesame TCI state, or may include a case where the DCI of the same contentis transmitted in association with different TCI states.

In addition, the above description may imply that the PS-PDCCH for thewake-up purpose is monitored only in some of configured monitoringoccasions even if monitoring occasions are designated by a monitoringperiodicity, offset, or the like in the SS set configuration for thePS-PDCCH.

Option 2) Nearest Monitoring Occasion Based on SS Set Configuration fromOn-Duration

In a case where the SS set configuration is also indicated for thePS-PDCCH for the wake-up purpose or an SS set configuration whichmonitors a PS-PDCCH indicating adaptation for an SS set configuration isindicated and in a case where a monitoring occasion is determined byparameters (e.g., monitoring periodicity, offset, etc.) in theconfiguration, regarding the PS-PDCCH for the wake-up purpose andassociated with a DRX operation, a monitoring occasion for the PS-PDCCHfor the wake-up purpose may be determined by the SS set configuration(otherwise, in a case where the DRX operation is not applied or in caseof a monitoring occasion of the SS set after the wake-up, the monitoringoccasion may be determined by a PS-PDCCH configuration, which may beused for on/off, configuration change, or the like for the configured SSset). For example, monitoring on the PS-PDCCH for the wake-up purposemay start in a monitoring occasion nearest to a DRX-on duration amongmonitoring occasions based on the SS set configuration. In this case,the nearest monitoring occasion may imply the nearest monitoringoccasion among monitoring occasions before the start of the on-duration,or may imply the nearest monitoring occasion among monitoring occasionsafter the start of the on-duration.

Alternatively, to ensure a processing time or the like for the PDCCH,the network may configure a specific offset (in this case, the offsetmay be applied before or after an on-duration starting point), and amonitoring occasion nearest from the offset may be defined as a startingpoint of PS-PDCCH monitoring.

This may be interpreted as a method of defining a monitoring startingpoint of a corresponding SS set in each DRX cycle of a DRX operationwhen the PS-PDCCH plays a role of not only wake-up but also SS setconfiguration adaptation (this may be also applied to other options). Inaddition, in this case, it may be assumed that an initial monitoringoccasion of each DRX cycle is used for the wake-up purpose.

Option 3) Reusing Existing SS Set Configuration as a Wake-Up Indication

Whether to wake up may be determined with monitoring on the existing SSset without having to additionally define a PS-PDCCH for wake-up. Forexample, a network may configure a specific SS set for the wake-uppurpose among SS sets configured in a conventional manner. In this case,a UE may perform only monitoring on the SS set in an on-duration of eachDRX cycle. Thereafter, upon detecting a PDCCH in the SS set, monitoringon another SS set configured in a corresponding active BWP may start.That is, a representative SS set may be configured by the network, andwhether to monitor another SS set may be determined (or assumed to bedetermined) by the UE according to whether the PDCCH is detected in therepresentative SS set.

Option 4) Wake-Up PS-PDCCH Monitoring on Existing SS Set

A network may be configured to use one or a plurality of the existing SSsets for the purpose of wake-up PS-PDCCH monitoring. When monitoring ona corresponding SS set is performed in an on-duration of a DRXoperation, a UE may perform monitoring on a PDCCH designated on an SSset configuration (e.g., a PDCCH designated depending on RNTI, DCI type)and a wake-up PS-PDCCH together. This may be implemented in such amanner that a configured PDCCH and a wake-up PS-PDCCH are monitored inall monitoring occasions or only a PS-PDCCH is monitored in a specificmonitoring occasion (e.g., a monitoring occasion existing in a specificrange from an on-duration starting point, a designed number ofmonitoring occasions from the on-duration starting point).

In addition, if both the existing configured PDCCH and the wake-upPS-PDCCH are monitored, it may be interpreted that detection of theexisting configured PDCCH indicates wake-up. In this case, upondetecting one of the PS-PDCCH and the existing configured PDCCH, the UEmay perform monitoring on another SS set.

Alternatively, the existing configured PDCCH may imply wake-up for allconfigured SS sets, and the wake-up PDCCH may imply wake-up for specificSS set(s).

In order to decrease complexity in this operation, it may be assumedthat a size of DCI of the PS-PDCCH is equal to that of DCI monitored ina corresponding SS set. In this case, the wake-up PS-PDCCH and DCIconfigured to be monitored in the SS set may be identified by RNTI orthe like.

<PS-PDCCH for PDCCH Monitoring Adaptation>

A PS-PDCCH may be used for not only wake-up but also adaptation for amonitoring operation of a PDCCH. For example, the PS-PDCCH for PDCCHmonitoring adaptation may be used for dynamic adaptation of an SS setconfiguration. As described above, the SS set configuration adaptationmay dynamically configure on/off for each SS set, and if associated witha DRX operation, a first monitoring occasion (of an SS set adaptationPS-PDCCH) in each DRX cycle may operate as wake-up or go-to-sleep. Thepresent disclosure proposes a method for implementing this.

1. Wake-up purpose

A. As described above, a first monitoring occasion of an SS setadaptation PS-PDCCH in a DRX cycle may be interpreted as a wake-upsignal in terms of determining whether to perform monitoring in the DRXcycle.

i. Whether to wake up may be determined in a first monitoring occasionor may be determined in a plurality of monitoring occasions. Beingdetermined in the plurality of monitoring occasions may imply that a UEdetermines the number of monitoring occasions, periodicity, or the likeof an SS set adaptation PS-PDCCH by a configuration (e.g., the number ofmonitoring occasions, a monitoring duration, etc.) predefined orconfigured by a network.

This may imply that the UE can perform a sleep operation during theremaining duration of a corresponding DRX cycle if the SS set adaptationPS-PDCCH is not detected in a corresponding determined duration.

ii. Additionally, a plurality of monitoring durations of an SS setadaptation PS-PDCCH for wake-up may be configured in one on-duration.For example, the UE may perform monitoring on the SS set adaptationPS-PDCCH when a DRX cycle starts, and may perform a sleep operationuntil a next monitoring duration of the SS set adaptation PS-PDCCH uponfailing in detection of the PS-PDCCH.

B. If the SS set adaptation PS-PDCCH determines whether to perform PDCCHmonitoring, the UE may perform only monitoring on the SS set adaptationPS-PDCCH in each DRX cycle, and may determine SS set(s) to be monitoredat a later time according to information in corresponding DCI upondetecting the SS set adaptation PS-PDCCH.

2. Go-to-Sleep (GTS) Purpose

The SS set adaptation PS-PDCCH may be used for the GTS purpose.

If the PS-PDCCH for the GTS purpose (without additional wake-up)operates in association with a DRX operation, the UE may performmonitoring on configured SS sets in a DRX on-duration, and may beindicated to turn specific SS set(s) off by a PS-PDCCH playing a role ofGTS. Herein, the GTS may imply an operation result of the PS-PDCCH, andan actual PS-PDCCH may be an SS set adaptation PS-PDCCH detected in amonitoring occasion of an SS set for SS set adaptation.

The following drawings were created to explain a specific example of thepresent specification. The names of specific devices described in thedrawings or the names of specific signals/messages/fields are presentedby way of example, so that the technical features of the presentspecification are not limited to the specific names used in thefollowing drawings.

FIG. 15 exemplifies reception of a PS-PDCCH used for GTS and anoperation of a UE according thereto. Referring to FIG. 15, the UE mayreceive/detect a PS-PDCCH for GTS while monitoring search space (SS)sets configured in the DRX on-duration. For example, the PS-PDCCH mayindicate monitoring off for search space #2 among search spaces #1 and2.

Then, the UE may skip monitoring for search space #2 after the PS-PDCCH.

Since the GTS implies a monitoring skip for the SS set,disadvantageously, it is difficult to cope with upon generation of datato be transmitted to a corresponding UE in a monitoring skip duration.To solve this, the following method may be taken into account.

Method 1) If monitoring of specific SS set(s) is skipped by an SS setadaptation PS-PDCCH, a duration to be skipped may be predefined or maybe indicated by a network. For example, a GTS timer may be configured,and monitoring on the SS set(s) may be resumed if this timer expires.

Method 2) If monitoring of specific SS set(s) is skipped by an SS setadaptation PS-PDCCH, monitoring on the SS set adaptation PS-PDCCH may becontinuously maintained. This implies that wake-up for SS set(s) ofwhich monitoring is being skipped may be indicated by using the SS setadaptation PS-PDCCH. In this case, a monitoring configuration for the SSset adaptation PS-PDCCH may conform to a configuration for the existingSS set adaptation PS-PDCCH, or a configuration at a specific conditionmay be predefined or configured additionally. Additionally, the method 2may also be applied limitedly only when monitoring of all SS setsconfigured by the GTS is skipped.

3. SS Set Configuration Adaptation Purpose

The SS set adaptation PS-PDCCH may be generally used for the purpose ofdynamic adaptation for a SS set configuration. This may imply that theaforementioned PS-PDCCH for the wake-up purpose or GTS purpose is partof the PS-PDCCH for the SS set configuration adaptation purpose. Thatis, the PS-PDCCH for the SS set configuration adaptation purpose may beused for the wake-up or GTS purpose according to a configuration in DCI.

On/off of SS set monitoring may be performed by the following methods.

A PS-PDCCH may indicate whether to perform monitoring on a configured SSset, and may be implemented in the following manner.

1) Bitmap: In NR, a network may configure up to 10 SS sets for each BWP.

Therefore, whether to perform monitoring on each SS set may be indicatedby using a bitmap corresponding to the maximum number of SS sets. Forexample, when four SS sets are configured for each BWP, it is possibleto indicate whether to monitor each SS set using a 4-bit bitmap. Eachbit of the bitmap corresponds to a different SS set, and when it has aspecific value (for example, 1), it may indicate to monitor (or notmonitor) the corresponding SS set.

2) Combination indication: In order to reduce the number of informationbits, the network may use higher layer signaling such as RRC or the liketo configure an SS set group simultaneously performing on/off, and mayuse an indication field in the PS-PDCCH to indicate whether to performmonitoring for each SS set group.

3) In another method, the network may configure SS set(s) capable ofperforming(applying) monitoring on/off through higher layer signaling orthe like, and may indicate monitoring on/off based on a bitmap or indexfor the SS sets. In order to fix the number of information bits,monitoring on/off may be predefined for only a predefined number of SSsets or may be indicated by the network. For example, it may bepredefined that SS set monitoring on/off is possible only for 4 SS sets,and the network may configure 4 SS sets among configured SS sets throughhigher layer signaling or the like. Thereafter, SS set(s) performing (orskipping) monitoring may be indicated by using a 2-bit indication or4-bit bitmap or the like in the PS-PDCCH.

FIG. 16 illustrates a method for monitoring a physical downlink controlchannel (PDCCH) of a UE.

Referring to FIG. 16, the UE monitors a PS-PDCCH that notifies powersaving (PS) information in a discontinuous reception (DRX)-on duration(S100).

The UE performs PDCCH monitoring in the DRX-on duration based on thedetected PS-PDCCH (S200).

The PS-PDCCH may include information informing a specific search spaceset (or a specific search space) among a plurality of search space setsconfigured for the DRX-on duration.

For example, the PS-PDCCH may include a bitmap informing the specificsearch space set.

The network may provide the UE with a higher layer signal informing apredetermined number of search space sets to which PDCCH monitoringon/off can be applied among a plurality of search space sets configuredfor the DRX-on duration. Thereafter, a bitmap informing the specificsearch space set among the predetermined number of search space sets maybe provided to the UE through the PS-PDCCH. The number of bits of thebitmap may be determined based on the predetermined number. For example,if the predetermined number of search space sets is four, it may bedetermined as 4 bits or as 2 bits.

The UE may monitor the PDCCH in search spaces other than the specificsearch space set among the plurality of search space sets. That is,PDCCH monitoring may be skipped in the specific search space set.

A time interval for skipping the PDCCH monitoring in the specific searchspace set may be informed or predetermined by the network. For example,a timer (referred to as a GTS timer) may be set by the network, and whenthe GTS timer expires, monitoring of the specific search space set maybe resumed.

In the time interval for skipping the PDCCH monitoring, the UE maymaintain monitoring for another PS-PDCCH. Here, the another PS-PDCCH maybe a PS-PDCCH including information indicating to the UE to wake up forthe specific search space set. This means that a search space set forreceiving the PS-PDCCH informing a wake-up indication is continuouslymonitored (not sleep) despite the GTS.

The PS-PDCCH may further include a field indicating wake-up of the UE.

A time point at which PDCCH monitoring based on PS-PDCCH is applied maybe determined to be the same as a minimum applicable delay value appliedto cross-slot scheduling. For example, let assume that PDCCH and PDSCHare received on a carrier to which the same numerology is applied. Whenthe DCI (the PDCCH) scheduling the PDSCH is received in slot n, if thePDSCH scheduled by the DCI can be allocated only after slot n+K0, the K0may be referred to as a minimum applicable delay. When this minimumapplicable K0 is, for example, 2 slots, the time of applying the PDCCHmonitoring based on the PS-PDCCH (that is, the application time of thePS-PDCCH indicating SS set adaptation) can also be assumed to be 2 slotslater from the time of receiving the PS-PDCCH (DCI).

The network may provide the UE with a higher layer signal indicatingwhether to activate or deactivate the PDCCH monitoring skip in thesearch space indicated by the PS-PDCCH. The UE may skip PDCCH monitoringin the search space indicated by the PS-PDCCH only when the higher layersignal informs the activation (i.e., indicates that PDCCH monitoring canbe skipped).

FIG. 17 illustrates an operation method between a network and a UE.

Referring to FIG. 17, the network provides a configuration of searchspace sets to which PDCCH monitoring on/off can be applied to the UE(S171).

The UE receives a PS-PDCCH including a bitmap indicating a specificsearch space set among the search space sets (S172), and in the DRX onduration, monitor the PDCCH in the remaining search spaces except forthe specific search space set among the search space sets (S173). As aresult, it can be seen that the PS-PDCCH serves to inform go-to-sleep(GTS) for the specific search space set.

From a network point of view, after transmitting a PS-PDCCH indicatingpower saving (PS) information in a discontinuous reception (DRX)-onduration (e.g., after transmitting a PS-PDCCH including a bitmapindicating a specific search space set among the search space sets), thenetwork may transmit the PDCCH, to the UE, in the DRX-on duration basedon the PS-PDCCH (e.g., for the UE, the network may transmit the PDCCH inthe remaining search spaces except for the specific search space setamong the search space sets).

<Monitoring Periodicity Control>

A network may adjust a monitoring periodicity of specific SS set(s) byusing a specific field in a PS-PDCCH. This may be implemented in such amanner that monitoring on part of the existing monitoring occasions isskipped or in such a manner that a monitoring periodicity is changed.

When the part of monitoring occasions is skipped, a scheme of indicatinga rule for the skip (e.g., the skip of odd slots or the skip of evenslots) or a scheme of indicating a skip duration may be used.

Such a scheme may also be applied to an aggregation level and the numberof candidates to be monitored in each SS set.

When a PS-PDCCH for the purpose of the SS set configuration adaptationoperates in a non-DRX operation as an additional operation, skipping ofmonitoring on all configured SS sets may be interpreted as newlydefining the same operation as a DRX operation, which may causeunnecessary procedure execution of the network and the UE, a complexityincrease, or the like. Therefore, it may be assumed in the presentdisclosure that an operation of turning on/off all configured SS sets isnot performed in the non-DRX operation. This may be interpreted as arestriction for some of functions of the PS-PDCCH for the purpose of SSset configuration adaptation in the non-DRX operation.

<Time Point of Applying PS-PDCCH Information>

It shall be determined from which time point a PS-PDCCH for theaforementioned PDCCH monitoring adaptation will be applied. To this end,a time point of applying the P-PDCCH may be configured by using at leastone of the following methods. The methods proposed below may beimplemented alone or in combination.

In addition, the following methods may be applied differently dependingon the purpose of the PS-PDCCH. For example, methods 1, 2, and 3 belowmay be used in a PS-PDCCH for wake-up, and a method 4 below may be usedin a PS-PDCCH for GTS.

In addition, the following methods may be applied in the same manner notonly to a PS-PDCCH for PDCCH monitoring adaptation but also to aPS-PDCCH for other purposes (e.g., antenna adaptation, BWP/SCelloperation, etc.). For example, in case of the antenna adaptation, a timepoint of applying the PS-PDCCH may be determined by adding a delay valuerelated to antenna switching to an offset proposed below.

Method 1. Next Slot of PS-PDCCH Reception Slot

As a simple method, a UE may assume that power saving related content(e.g., SS set on/off, monitoring periodicity change, etc.) indicated bya PS-PDCCH is applied from a slot next to a slot in which the PS-PDCCHis received.

For example, assume that the PS-PDCCH is received in a slot n, andmonitoring on all SS sets is skipped in the PS-PDCCH. In this case, theUE may skip monitoring on configured SS set(s) from a slot n+1. However,upon receiving DCI for PDSCH scheduling in the slot n, an operation ofreceiving the PDSCH may be performed even after the slot n. A techniqueof the method 1 also includes a technique applied from a symbol next toa CORESET which has received the PS-PDCCH, and a technique forimplementing this may be applied in the same manner as described above.

Method 2. Based on PDCCH Decoding Capacity of UE

A time point of applying a PS-PDCCH may be determined based on PDCCHdecoding capacity of a UE. This may be effective in a sense thatunnecessary buffering or the like can be reduced in an operation such aswake-up or the like. For example, when the UE requires two slots forPDCCH decoding (and TCI application), the UE may assume that a timepoint of applying a PS-PDCCH received in a slot n is a slot n+2.

Method 3. Determining ACK(/NACK)-Based Timing

When ACK transmission for a PS-PDCCH is introduced, a time point ofapplying the PS-PDCCH may be determined by considering a delay by whichcorresponding ACK arrives at a network. For example, when a timerequired when the network receives ACK for the PS-PDCCH from a timepoint at which a UE receives the PS-PDCCH is 7 slots, the UE may assumethat a time point of applying the PS-PDCCH received in a slot n is aslot n+7.

Method 4. PS-PDCCH Reception Slot

Irrespective of a reception position of a PS-PDCCH in a slot, it may beassumed that information of a PS-PDCCH is applied from the slot. Forexample, when the present disclosure is applied to a PS-PDCCH, when anSS set of which monitoring is skipped by the PS-PDCCH is detected in acorresponding slot, and when decoding on a candidate of the skipped SSset is stopped or a PDSCH is scheduled, corresponding PDSCH receptionmay be skipped.

Method 5. Additionally, it may be assumed that, when minimum applicableKO in cross-slot scheduling is configured, a time point of applying aPS-PDCCH for SS set adaptation is determined by an application delay ofthe minimum application KO. For example, it may be assumed that, whenthe application delay of the minimum applicable KO is 2 slots, a timepoint of applying a PS-PDCCH indicating the SS set adaptation is 2 slotsafter a time point of receiving corresponding DCI.

<PS SS Set Monitoring>

A network may determine whether to apply a power saving scheme byconsidering a traffic situation of the network, a service type of a UE,a mobility of the UE, a battery situation, or the like. These factorsmay change dynamically, which may imply that whether to apply the powersaving scheme shall also be changeable dynamically. For this reason, thepresent disclosure proposes to dynamically configure whether to applythe power saving scheme, which can be implemented by using the followingmethod.

The network may indicate a power saving scheme list and/or CORESET/SSset configuration for PS-PDCCH transmission/reception or the like to theUE. In this case, the configuration of the CORESET/SS set or the likemay be indicated alone or in combination according to the power savingscheme (combination).

Whether to perform monitoring on a corresponding CORESET/SS set may beindicated by signaling such as RRC/MAC CE or the like by the network.That is, the UE may perform monitoring on a PS-PDCCH after activation ofCORESET/SS set monitoring is indicated by additional RRC/MAC CEsignaling, rather than performing monitoring based on only theCORESET/SS set configuration for power saving. Deactivation formonitoring may also be indicated by RRC/MAC CE signaling.

For example, the network may indicate a plurality of CORESET/SS setscapable of monitoring a PS-PDCCH through RRC signaling or the like, andmay indicate a time point at which the UE performs monitoring and theCORESET/SS set to the UE through MAC CE signaling. Alternatively,CORESET/SS set candidate signaling may be indicated through a broadcastsignal (e.g., system information (SIB)) to reduce a signaling overheador the like.

FIG. 18 illustrates a wireless device applicable to the presentspecification.

Referring to FIG. 18, a first wireless device 100 and a second wirelessdevice 200 may transmit radio signals through a variety of RATs (e.g.,LTE and NR).

The first wireless device 100 may include one or more processors 102 andone or more memories 104 and additionally further include one or moretransceivers 106 and/or one or more antennas 108. The processors 102 maycontrol the memory 104 and/or the transceivers 106 and may be configuredto implement the descriptions, functions, procedures, proposals,methods, and/or operational flowcharts disclosed in this document. Forexample, the processors 102 may process information within the memory104 to generate first information/signals and then transmit radiosignals including the first information/signals through the transceivers106. In addition, the processor 102 may receive radio signals includingsecond information/signals through the transceiver 106 and then storeinformation obtained by processing the second information/signals in thememory 104. The memory 104 may be connected to the processor 102 and maystore a variety of information related to operations of the processor102. For example, the memory 104 may store software code includingcommands for performing a part or the entirety of processes controlledby the processor 102 or for performing the descriptions, functions,procedures, proposals, methods, and/or operational flowcharts disclosedin this document. Herein, the processor 102 and the memory 104 may be apart of a communication modem/circuit/chip designed to implement RAT(e.g., LTE or NR). The transceiver 106 may be connected to the processor102 and transmit and/or receive radio signals through one or moreantennas 108. The transceiver 106 may include a transmitter and/or areceiver. The transceiver 106 may be interchangeably used with a radiofrequency (RF) unit. In the present specification, the wireless devicemay represent a communication modem/circuit/chip.

The second wireless device 200 may include one or more processors 202and one or more memories 204 and additionally further include one ormore transceivers 206 and/or one or more antennas 208. The processor 202may control the memory 204 and/or the transceiver 206 and may beconfigured to implement the descriptions, functions, procedures,proposals, methods, and/or operational flowcharts disclosed in thisdocument. For example, the processor 202 may process information withinthe memory 204 to generate third information/signals and then transmitradio signals including the third information/signals through thetransceiver 206. In addition, the processor 202 may receive radiosignals including fourth information/signals through the transceiver 106and then store information obtained by processing the fourthinformation/signals in the memory 204. The memory 204 may be connectedto the processor 202 and may store a variety of information related tooperations of the processor 202. For example, the memory 204 may storesoftware code including commands for performing a part or the entiretyof processes controlled by the processor 202 or for performing thedescriptions, functions, procedures, proposals, methods, and/oroperational flowcharts disclosed in this document. Herein, the processor202 and the memory 204 may be a part of a communicationmodem/circuit/chip designed to implement RAT (e.g., LTE or NR). Thetransceiver 206 may be connected to the processor 202 and transmitand/or receive radio signals through one or more antennas 208. Thetransceiver 206 may include a transmitter and/or a receiver. Thetransceiver 206 may be interchangeably used with an RF unit. In thepresent specification, the wireless device may represent a communicationmodem/circuit/chip.

Hereinafter, hardware elements of the wireless devices 100 and 200 willbe described more specifically. One or more protocol layers may beimplemented by, without being limited to, one or more processors 102 and202. For example, the one or more processors 102 and 202 may implementone or more layers (e.g., functional layers such as PHY, MAC, RLC, PDCP,RRC, and SDAP). The one or more processors 102 and 202 may generate oneor more Protocol Data Units (PDUs) and/or one or more Service Data Unit(SDUs) according to the descriptions, functions, procedures, proposals,methods, and/or operational flowcharts disclosed in this document. Theone or more processors 102 and 202 may generate messages, controlinformation, data, or information according to the descriptions,functions, procedures, proposals, methods, and/or operational flowchartsdisclosed in this document. The one or more processors 102 and 202 maygenerate signals (e.g., baseband signals) including PDUs, SDUs,messages, control information, data, or information according to thedescriptions, functions, procedures, proposals, methods, and/oroperational flowcharts disclosed in this document and provide thegenerated signals to the one or more transceivers 106 and 206. The oneor more processors 102 and 202 may receive the signals (e.g., basebandsignals) from the one or more transceivers 106 and 206 and acquire thePDUs, SDUs, messages, control information, data, or informationaccording to the descriptions, functions, procedures, proposals,methods, and/or operational flowcharts disclosed in this document.

The one or more processors 102 and 202 may be referred to ascontrollers, microcontrollers, microprocessors, or microcomputers. Theone or more processors 102 and 202 may be implemented by hardware,firmware, software, or a combination thereof. For example, one or moreApplication Specific Integrated Circuits (ASICs), one or more DigitalSignal Processors (DSPs), one or more Digital Signal Processing Devices(DSPDs), one or more Programmable Logic Devices (PLDs), or one or moreField Programmable Gate Arrays (FPGAs) may be included in the one ormore processors 102 and 202. The one or more processors 102 and 202 maybe implemented with at least one computer readable medium (CRM)including instructions to be executed by at least one processor. Thatis, the at least one CRM including the instructions to be executed bythe at least one processor may perform operations including receiving anoffset based on a starting slot of a DRX-on duration and monitoring aPS-PDCCH notifying of power saving (PS) information in a time windowbetween the starting slot and a time based on the offset.

That is, at least one computer readable medium (CRM) includinginstructions based on being executed by at least one processor mayperform the following steps. Monitoring a PS-PDCCH informing of powersaving (PS) information in a discontinuous reception (DRX)-on durationand performing PDCCH monitoring in the DRX-on duration based on thedetected PS-PDCCH. The PS-PDCCH includes information indicating aspecific search space set among a plurality of search space setsconfigured for the DRX-on duration, and the UE monitors the PDCCH inremaining search spaces other than the specific search space set amongthe plurality of search space sets.

The descriptions, functions, procedures, proposals, methods, and/oroperational flowcharts disclosed in this document may be implementedusing firmware or software and the firmware or software may beconfigured to include the modules, procedures, or functions. Firmware orsoftware configured to perform the descriptions, functions, procedures,proposals, methods, and/or operational flowcharts disclosed in thisdocument may be included in the one or more processors 102 and 202 orstored in the one or more memories 104 and 204 so as to be driven by theone or more processors 102 and 202. The descriptions, functions,procedures, proposals, methods, and/or operational flowcharts disclosedin this document may be implemented using firmware or software in theform of code, commands, and/or a set of commands.

The one or more memories 104 and 204 may be connected to the one or moreprocessors 102 and 202 and store various types of data, signals,messages, information, programs, code, instructions, and/or commands.The one or more memories 104 and 204 may be configured by Read-OnlyMemories (ROMs), Random Access Memories (RAMs), Electrically ErasableProgrammable Read-Only Memories (EPROMs), flash memories, hard drives,registers, cash memories, computer-readable storage media, and/orcombinations thereof. The one or more memories 104 and 204 may belocated at the interior and/or exterior of the one or more processors102 and 202. In addition, the one or more memories 104 and 204 may beconnected to the one or more processors 102 and 202 through varioustechnologies such as wired or wireless connection.

The one or more transceivers 106 and 206 may transmit user data, controlinformation, and/or radio signals/channels, mentioned in the methodsand/or operational flowcharts of this document, to one or more otherdevices. The one or more transceivers 106 and 206 may receive user data,control information, and/or radio signals/channels, mentioned in thedescriptions, functions, procedures, proposals, methods, and/oroperational flowcharts disclosed in this document, from one or moreother devices. For example, the one or more transceivers 106 and 206 maybe connected to the one or more processors 102 and 202 and transmit andreceive radio signals. For example, the one or more processors 102 and202 may perform control so that the one or more transceivers 106 and 206may transmit user data, control information, or radio signals to one ormore other devices. In addition, the one or more processors 102 and 202may perform control so that the one or more transceivers 106 and 206 mayreceive user data, control information, or radio signals from one ormore other devices. In addition, the one or more transceivers 106 and206 may be connected to the one or more antennas 108 and 208 and the oneor more transceivers 106 and 206 may be configured to transmit andreceive user data, control information, and/or radio signals/channels,mentioned in the descriptions, functions, procedures, proposals,methods, and/or operational flowcharts disclosed in this document,through the one or more antennas 108 and 208. In this document, the oneor more antennas may be a plurality of physical antennas or a pluralityof logical antennas (e.g., antenna ports). The one or more transceivers106 and 206 may convert received radio signals/channels etc. from RFband signals into baseband signals in order to process received userdata, control information, radio signals/channels, etc. using the one ormore processors 102 and 202. The one or more transceivers 106 and 206may convert the user data, control information, radio signals/channels,etc. processed using the one or more processors 102 and 202 from thebase band signals into the RF band signals. To this end, the one or moretransceivers 106 and 206 may include (analog) oscillators and/orfilters.

FIG. 19 shows an example of a structure of a signal processing module.Herein, signal processing may be performed in the processors 102 and 202of FIG. 18.

Referring to FIG. 19, the transmitting device (e.g., a processor, theprocessor and a memory, or the processor and a transceiver) in a UE orBS may include a scrambler 301, a modulator 302, a layer mapper 303, anantenna port mapper 304, a resource block mapper 305, and a signalgenerator 306.

The transmitting device can transmit one or more codewords. Coded bitsin each codeword are scrambled by the corresponding scrambler 301 andtransmitted over a physical channel. A codeword may be referred to as adata string and may be equivalent to a transport block which is a datablock provided by the MAC layer.

Scrambled bits are modulated into complex-valued modulation symbols bythe corresponding modulator 302. The modulator 302 can modulate thescrambled bits according to a modulation scheme to arrangecomplex-valued modulation symbols representing positions on a signalconstellation. The modulation scheme is not limited and m-PSK (m-PhaseShift Keying) or m-QAM (m-Quadrature Amplitude Modulation) may be usedto modulate the coded data. The modulator may be referred to as amodulation mapper.

The complex-valued modulation symbols can be mapped to one or moretransport layers by the layer mapper 303. Complex-valued modulationsymbols on each layer can be mapped by the antenna port mapper 304 fortransmission on an antenna port.

Each resource block mapper 305 can map complex-valued modulation symbolswith respect to each antenna port to appropriate resource elements in avirtual resource block allocated for transmission. The resource blockmapper can map the virtual resource block to a physical resource blockaccording to an appropriate mapping scheme. The resource block mapper305 can allocate complex-valued modulation symbols with respect to eachantenna port to appropriate subcarriers and multiplex the complex-valuedmodulation symbols according to a user.

Signal generator 306 can modulate complex-valued modulation symbols withrespect to each antenna port, that is, antenna-specific symbols,according to a specific modulation scheme, for example, OFDM (OrthogonalFrequency Division Multiplexing), to generate a complex-valued timedomain OFDM symbol signal. The signal generator can perform IFFT(Inverse Fast Fourier Transform) on the antenna-specific symbols, and aCP (cyclic Prefix) can be inserted into time domain symbols on whichIFFT has been performed. OFDM symbols are subjected to digital-analogconversion and frequency up-conversion and then transmitted to thereceiving device through each transmission antenna. The signal generatormay include an IFFT module, a CP inserting unit, a digital-to-analogconverter (DAC) and a frequency upconverter.

FIG. 20 shows another example of a structure of a signal processingmodule in a transmitting device. Herein, signal processing may beperformed in a processor of a UE/BS, such as the processors 102 and 202of FIG. 18.

Referring to FIG. 20, the transmitting device (e.g., a processor, theprocessor and a memory, or the processor and a transceiver) in the UE orthe BS may include a scrambler 401, a modulator 402, a layer mapper 403,a precoder 404, a resource block mapper 405, and a signal generator 406.

The transmitting device can scramble coded bits in a codeword by thecorresponding scrambler 401 and then transmit the scrambled coded bitsthrough a physical channel.

Scrambled bits are modulated into complex-valued modulation symbols bythe corresponding modulator 402. The modulator can modulate thescrambled bits according to a predetermined modulation scheme to arrangecomplex-valued modulation symbols representing positions on a signalconstellation. The modulation scheme is not limited and pi/2-BPSK(pi/2-Binary Phase Shift Keying), m-PSK (m-Phase Shift Keying) or m-QAM(m-Quadrature Amplitude Modulation) may be used to modulate the codeddata.

The complex-valued modulation symbols can be mapped to one or moretransport layers by the layer mapper 403.

Complex-valued modulation symbols on each layer can be precoded by theprecoder 404 for transmission on an antenna port. Here, the precoder mayperform transform precoding on the complex-valued modulation symbols andthen perform precoding. Alternatively, the precoder may performprecoding without performing transform precoding. The precoder 404 canprocess the complex-valued modulation symbols according to MIMO usingmultiple transmission antennas to output antenna-specific symbols anddistribute the antenna-specific symbols to the corresponding resourceblock mapper 405. An output z of the precoder 404 can be obtained bymultiplying an output y of the layer mapper 403 by an N×M precodingmatrix W. Here, N is the number of antenna ports and M is the number oflayers.

Each resource block mapper 405 maps complex-valued modulation symbolswith respect to each antenna port to appropriate resource elements in avirtual resource block allocated for transmission.

The resource block mapper 405 can allocate complex-valued modulationsymbols to appropriate subcarriers and multiplex the complex-valuedmodulation symbols according to a user.

Signal generator 406 can modulate complex-valued modulation symbolsaccording to a specific modulation scheme, for example, OFDM, togenerate a complex-valued time domain OFDM symbol signal. The signalgenerator 406 can perform IFFT (Inverse Fast Fourier Transform) onantenna-specific symbols, and a CP (cyclic Prefix) can be inserted intotime domain symbols on which IFFT has been performed. OFDM symbols aresubjected to digital-analog conversion and frequency up-conversion andthen transmitted to the receiving device through each transmissionantenna. The signal generator 406 may include an IFFT module, a CPinserting unit, a digital-to-analog converter (DAC) and a frequencyupconverter.

The signal processing procedure of the receiving device may be reverseto the signal processing procedure of the transmitting device.Specifically, the processor of the transmitting device decodes anddemodulates RF signals received through antenna ports of thetransceiver. The receiving device may include a plurality of receptionantennas, and signals received through the reception antennas arerestored to baseband signals, and then multiplexed and demodulatedaccording to MIMO to be restored to a data string intended to betransmitted by the transmitting device. The receiving device may includea signal restoration unit that restores received signals to basebandsignals, a multiplexer for combining and multiplexing received signals,and a channel demodulator for demodulating multiplexed signal stringsinto corresponding codewords. The signal restoration unit, themultiplexer and the channel demodulator may be configured as anintegrated module or independent modules for executing functionsthereof. More specifically, the signal restoration unit may include ananalog-to-digital converter (ADC) for converting an analog signal into adigital signal, a CP removal unit that removes a CP from the digitalsignal, an FET module for applying FFT (fast Fourier transform) to thesignal from which the CP has been removed to output frequency domainsymbols, and a resource element demapper/equalizer for restoring thefrequency domain symbols to antenna-specific symbols. Theantenna-specific symbols are restored to transport layers by themultiplexer and the transport layers are restored by the channeldemodulator to codewords intended to be transmitted by the transmittingdevice.

FIG. 21 illustrates an example of a wireless communication deviceaccording to an implementation example of the present disclosure.

Referring to FIG. 21, the wireless communication device, for example, aterminal may include at least one of a processor 2310 such as a digitalsignal processor (DSP) or a microprocessor, a transceiver 2335, a powermanagement module 2305, an antenna 2340, a battery 2355, a display 2315,a keypad 2320, a global positioning system (GPS) chip 2360, a sensor2365, a memory 2330, a subscriber identification module (SIM) card 2325,a speaker 2345 and a microphone 2350. A plurality of antennas and aplurality of processors may be provided.

The processor 2310 can implement functions, procedures and methodsdescribed in the present description. The processor 2310 in FIG. 21 maybe the processors 1811 and 1821 in FIG. 18.

The memory 2330 is connected to the processor 2310 and storesinformation related to operations of the processor. The memory may belocated inside or outside the processor and connected to the processorthrough various techniques such as wired connection and wirelessconnection. The memory 2330 in FIG. 21 may be the memories 1813 and 1823in FIG. 18.

A user can input various types of information such as telephone numbersusing various techniques such as pressing buttons of the keypad 2320 oractivating sound using the microphone 2350. The processor 2310 canreceive and process user information and execute an appropriate functionsuch as calling using an input telephone number. In some scenarios, datacan be retrieved from the SIM card 2325 or the memory 2330 to executeappropriate functions. In some scenarios, the processor 2310 can displayvarious types of information and data on the display 2315 for userconvenience.

The transceiver 2335 is connected to the processor 2310 and transmitand/or receive RF signals. The processor can control the transceiver inorder to start communication or to transmit RF signals including varioustypes of information or data such as voice communication data. Thetransceiver includes a transmitter and a receiver for transmitting andreceiving RF signals. The antenna 2340 can facilitate transmission andreception of RF signals. In some implementation examples, when thetransceiver receives an RF signal, the transceiver can forward andconvert the signal into a baseband frequency for processing performed bythe processor. The signal can be processed through various techniquessuch as converting into audible or readable information to be outputthrough the speaker 2345. The transceiver in FIG. 21 may be thetransceivers 1812 and 1822 in FIG. 18.

Although not shown in FIG. 21, various components such as a camera and auniversal serial bus (USB) port may be additionally included in theterminal. For example, the camera may be connected to the processor2310.

FIG. 21 is an example of implementation with respect to the terminal andimplementation examples of the present disclosure are not limitedthereto. The terminal need not essentially include all the componentsshown in FIG. 21. That is, some of the components, for example, thekeypad 2320, the GPS chip 2360, the sensor 2365 and the SIM card 2325may not be essential components. In this case, they may not be includedin the terminal.

FIG. 22 shows an example of a processor 2000.

Referring to FIG. 22, the processor 2000 may include a control channelmonitoring unit 2010 and a data channel receiving unit 2020. Theprocessor 2000 may execute the methods described in FIG. 15 to FIG. 17(from a perspective of a receiver). For example, the processor 2000 mayreceive an offset based on a starting slot of a DRX-on duration, and maymonitor a PS-PDCCH notifying of power saving (PS) information in a timewindow between the starting slot and a time based on the offset. Upondetecting/receiving a PDCCH including scheduling information in theDRX-on duration, a PDSCH may be received based on the PDCCH (or a PUSCHmay be transmitted). The processor 2000 may be an example of theprocessors 102 and 202 of FIG. 18.

FIG. 23 shows an example of a processor 3000.

Referring to FIG. 23, the processor 3000 may include a controlinformation/data generating module 3010 and a transmitting module 3020.The processor 3000 may execute the methods described in FIG. 15 to FIG.17 (from a perspective of a transceiver). For example, the processor3000 may generate an offset based on a starting slot of a DRX-onduration, and then may notify a UE about it. In addition, the processor3000 may transmit a PS-PDCCH notifying of power saving (PS) informationin a time window between the starting slot and a time based on theoffset. Thereafter, a PDCCH including scheduling information may betransmitted in the DRX-on duration, and a PDSCH may be transmitted or aPUSCH may be received based on the PDCCH. The processor 3000 may be anexample of the processors 102 and 202 of FIG. 18.

FIG. 24 shows another example of a wireless device.

Referring to FIG. 24, the wireless device may include one or moreprocessors 102 and 202, one or more memories 104 and 204, and one ormore transceivers 108 and 208.

The example of the wireless device described in FIG. 18 is differentfrom the example of the wireless described in FIG. 24 in that theprocessors 102 and 202 and the memories 104 and 204 are separated inFIG. 18 whereas the memories 104 and 204 are included in the processors102 and 202 in the example of FIG. 24. That is, the processor and thememory may constitute one chipset. That is, a chipset (a device of awireless communication system) may include a processor and a memorycoupled with the processor, wherein the processor is configured toreceive an offset based on a starting slot of a DRX-on duration and tomonitor a PS-PDCCH notifying of PS information in a time window betweenthe time slot and a time based on the offset.

FIG. 25 shows another example of a wireless device applied to thepresent specification. The wireless device may be implemented in variousforms according to a use-case/service.

Referring to FIG. 25, wireless devices 100 and 200 may correspond to thewireless devices 100 and 200 of FIG. 18 and may be configured by variouselements, components, units/portions, and/or modules. For example, eachof the wireless devices 100 and 200 may include a communication unit110, a control unit 120, a memory unit 130, and additional components140. The communication unit may include a communication circuit 112 andtransceiver(s) 114. For example, the communication circuit 112 mayinclude the one or more processors 102 and 202 and/or the one or morememories 104 and 204 of FIG. 18. For example, the transceiver(s) 114 mayinclude the one or more transceivers 106 and 206 and/or the one or moreantennas 108 and 208 of FIG. 18. The control unit 120 is electricallyconnected to the communication unit 110, the memory 130, and theadditional components 140 and controls overall operation of the wirelessdevices. For example, the control unit 120 may control anelectric/mechanical operation of the wireless device based onprograms/code/commands/information stored in the memory unit 130. Inaddition, the control unit 120 may transmit the information stored inthe memory unit 130 to the exterior (e.g., other communication devices)via the communication unit 110 through a wireless/wired interface orstore, in the memory unit 130, information received through thewireless/wired interface from the exterior (e.g., other communicationdevices) via the communication unit 110.

The additional components 140 may be variously configured according totypes of wireless devices. For example, the additional components 140may include at least one of a power unit/battery, input/output (I/O)unit, a driving unit, and a computing unit. The wireless device may beimplemented in the form of, without being limited to, the robot (100 aof FIG. 20), the vehicles (100 b-1 and 100 b-2 of FIG. 20), the XRdevice (100 c of FIG. 20), the hand-held device (100 d of FIG. 20), thehome appliance (100 e of FIG. 20), the IoT device (100 f of FIG. 20), adigital broadcast terminal, a hologram device, a public safety device,an MTC device, a medicine device, a fintech device (or a financedevice), a security device, a climate/environment device, the AIserver/device (400 of FIG. 20), the BSs (200 of FIG. 20), a networknode, etc. The wireless device may be used in a mobile or fixed placeaccording to a use-example/service.

In FIG. 25, the entirety of the various elements, components,units/portions, and/or modules in the wireless devices 100 and 200 maybe connected to each other through a wired interface or at least a partthereof may be wirelessly connected through the communication unit 110.For example, in each of the wireless devices 100 and 200, the controlunit 120 and the communication unit 110 may be connected by wire and thecontrol unit 120 and first units (e.g., 130 and 140) may be wirelesslyconnected through the communication unit 110. In addition, each element,component, unit/portion, and/or module within the wireless devices 100and 200 may further include one or more elements. For example, thecontrol unit 120 may be configured by a set of one or more processors.For example, the control unit 120 may be configured by a set of acommunication control processor, an application processor, an ElectronicControl Unit (ECU), a graphical processing unit, and a memory controlprocessor. For another example, the memory 130 may be configured by aRandom Access Memory (RAM), a Dynamic RAM (DRAM), a Read Only Memory(ROM)), a flash memory, a volatile memory, a non-volatile memory, and/ora combination thereof.

FIG. 26 illustrates a hand-held device applied to the presentspecification. The hand-held device may include a smartphone, asmartpad, a wearable device (e.g., a smartwatch or a smartglasses), or aportable computer (e.g., a notebook). The hand-held device may bereferred to as a mobile station (MS), a user terminal (UT), a MobileSubscriber Station (MSS), a Subscriber Station (SS), an Advanced MobileStation (AMS), or a Wireless Terminal (WT).

Referring to FIG. 26, a hand-held device 100 may include an antenna unit108, a communication unit 110, a control unit 120, a memory unit 130, apower supply unit 140 a, an interface unit 140 b, and an I/O unit 140 c.The antenna unit 108 may be configured as a part of the communicationunit 110. Blocks 110 to 130/140 a to 140 c respective correspond to theblocks 110 to 130/140 of FIG. 25.

The communication unit 110 may transmit and receive signals (e.g., dataand control signals) to and from other wireless devices or BSs. Thecontrol unit 120 may perform various operations by controllingconstituent elements of the hand-held device 100. The control unit 120may include an Application Processor (AP). The memory unit 130 may storedata/parameters/programs/code/commands needed to drive the hand-helddevice 100. In addition, the memory unit 130 may store input/outputdata/information. The power supply unit 140 a may supply power to thehand-held device 100 and include a wired/wireless charging circuit, abattery, etc. The interface unit 140 b may support connection of thehand-held device 100 to other external devices. The interface unit 140 bmay include various ports (e.g., an audio I/O port and a video I/O port)for connection with external devices. The I/O unit 140 c may input oroutput video information/signals, audio information/signals, data,and/or information input by a user. The I/O unit 140 c may include acamera, a microphone, a user input unit, a display unit 140 d, aspeaker, and/or a haptic module.

For example, in the case of data communication, the I/O unit 140 c mayacquire information/signals (e.g., touch, text, voice, images, or video)input by a user and the acquired information/signals may be stored inthe memory unit 130. The communication unit 110 may convert theinformation/signals stored in the memory into radio signals and transmitthe converted radio signals to other wireless devices directly or to aBS. In addition, the communication unit 110 may receive radio signalsfrom other wireless devices or the BS and then restore the receivedradio signals into original information/signals. The restoredinformation/signals may be stored in the memory unit 130 and may beoutput as various types (e.g., text, voice, images, video, or haptic)through the I/O unit 140 c.

FIG. 27 illustrates a communication system 1 applied to the presentspecification.

Referring to FIG. 27, a communication system 1 applied to the presentspecification includes wireless devices, Base Stations (BSs), and anetwork. Herein, the wireless devices represent devices performingcommunication using Radio Access Technology (RAT) (e.g., 5G New RAT(NR)) or Long-Term Evolution (LTE)) and may be referred to ascommunication/radio/5G devices. The wireless devices may include,without being limited to, a robot 100 a, vehicles 100 b-1 and 100 b-2,an eXtended Reality (XR) device 100 c, a hand-held device 100 d, a homeappliance 100 e, an Internet of Things (IoT) device 100 f, and anArtificial Intelligence (AI) device/server 400. For example, thevehicles may include a vehicle having a wireless communication function,an autonomous vehicle, and a vehicle capable of performing communicationbetween vehicles. Herein, the vehicles may include an Unmanned AerialVehicle (UAV) (e.g., a drone). The XR device may include an AugmentedReality (AR)/Virtual Reality (VR)/Mixed Reality (MR) device and may beimplemented in the form of a Head-Mounted Device (HMD), a Head-UpDisplay (HUD) mounted in a vehicle, a television, a smartphone, acomputer, a wearable device, a home appliance device, a digital signage,a vehicle, a robot, etc. The hand-held device may include a smartphone,a smartpad, a wearable device (e.g., a smartwatch or a smartglasses),and a computer (e.g., a notebook). The home appliance may include a TV,a refrigerator, and a washing machine. The IoT device may include asensor and a smartmeter. For example, the BSs and the network may beimplemented as wireless devices and a specific wireless device 200 a mayoperate as a BS/network node with respect to other wireless devices.

The wireless devices 100 a to 100 f may be connected to the network 300via the BSs 200. An AI technology may be applied to the wireless devices100 a to 100 f and the wireless devices 100 a to 100 f may be connectedto the AI server 400 via the network 300. The network 300 may beconfigured using a 3G network, a 4G (e.g., LTE) network, or a 5G (e.g.,NR) network. Although the wireless devices 100 a to 100 f maycommunicate with each other through the BSs 200/network 300, thewireless devices 100 a to 100 f may perform direct communication (e.g.,sidelink communication) with each other without passing through theBSs/network. For example, the vehicles 100 b-1 and 100 b-2 may performdirect communication (e.g. Vehicle-to-Vehicle(V2V)/Vehicle-to-everything (V2X) communication). In addition, the IoTdevice (e.g., a sensor) may perform direct communication with other IoTdevices (e.g., sensors) or other wireless devices 100 a to 100 f.

Wireless communication/connections 150 a, 150 b, or 150 c may beestablished between the wireless devices 100 a to 100 f/BS 200, or BS200/BS 200. Herein, the wireless communication/connections may beestablished through various RATs (e.g., 5G NR) such as uplink/downlinkcommunication 150 a, sidelink communication 150 b (or, D2Dcommunication), or inter BS communication(e.g. relay, Integrated AccessBackhaul(IAB)). The wireless devices and the BSs/the wireless devicesmay transmit/receive radio signals to/from each other through thewireless communication/connections 150 a and 150 b. For example, thewireless communication/connections 150 a and 150 b may transmit/receivesignals through various physical channels. To this end, at least a partof various configuration information configuring processes, varioussignal processing processes (e.g., channel encoding/decoding,modulation/demodulation, and resource mapping/demapping), and resourceallocating processes, for transmitting/receiving radio signals, may beperformed based on the various proposals of the present disclosure.

Meanwhile, the NR supports multiple numerologies (or subcarrier spacing(SCS)) for supporting diverse 5G services. For example, if the SCS is 15kHz, a wide area of the conventional cellular bands may be supported. Ifthe SCS is 30 kHz/60 kHz, a dense-urban, lower latency, and widercarrier bandwidth is supported. If the SCS is 60 kHz or higher, abandwidth greater than 24.25 GHz is used in order to overcome phasenoise.

An NR frequency band may be defined as a frequency range of two types(FR1, FR2). Values of the frequency range may be changed. For example,the frequency range of the two types (FR1, FR2) may be as shown below inTable 7. For convenience of explanation, among the frequency ranges thatare used in an NR system, FR1 may mean a “sub 6 GHz range”, and FR2 maymean an “above 6 GHz range” and may also be referred to as a millimeterwave (mmW).

TABLE 7 Frequency Range Corresponding frequency Subcarrier Spacingdesignation range (SCS) FR1 450MHz−6000MHz 15, 30, 60kHz FR224250MHz−52600MHz 60, 120, 240kHz

As described above, the values of the frequency ranges in the NR systemmay be changed. For example, as shown in Table 8 below, FR1 may includea band in the range of 410 MHz to 7125 MHz. That is, FR1 may include afrequency band of at least 6 GHz (or 5850, 5900, 5925 MHz, and so on).For example, a frequency band of at least 6 GHz (or 5850, 5900, 5925MHz, and so on) included in FR1 may include an unlicensed band. Theunlicensed band may be used for diverse purposes, e.g., the unlicensedband for vehicle-specific communication (e.g., automated driving).

Frequency Range Corresponding Subcarrier designation frequency rangeSpacing (SCS) FR1 410M1Hz−7125MHz 15, 30, 60kHz FR2 24250MHz−52600MHz60, 120, 240kHz

FIG. 28 illustrates a vehicle or an autonomous vehicle applicable to thepresent specification. The vehicle or autonomous vehicle may beimplemented by a mobile robot, a car, a train, a manned/unmanned AerialVehicle (AV), a ship, etc.

Referring to FIG. 28, a vehicle or autonomous vehicle 100 may include anantenna unit 108, a communication unit 110, a control unit 120, adriving unit 140 a, a power supply unit 140 b, a sensor unit 140 c, andan autonomous driving unit 140 d. The antenna unit 108 may be configuredas a part of the communication unit 110. The blocks 110/130/140 a to 140d respectively correspond to the blocks 110/130/140 of FIG. 25.

The communication unit 110 may transmit and receive signals (e.g., dataand control signals) to and from external devices such as othervehicles, BSs (e.g., gNBs and road side units), and servers. The controlunit 120 may perform various operations by controlling elements of thevehicle or the autonomous vehicle 100. The control unit 120 may includean Electronic Control Unit (ECU). The driving unit 140 a may cause thevehicle or the autonomous vehicle 100 to drive on a road. The drivingunit 140 a may include an engine, a motor, a powertrain, a wheel, abrake, a steering device, etc. The power supply unit 140 b may supplypower to the vehicle or the autonomous vehicle 100 and include awired/wireless charging circuit, a battery, etc. The sensor unit 140 cmay acquire a vehicle state, ambient environment information, userinformation, etc. The sensor unit 140 c may include an InertialMeasurement Unit (IMU) sensor, a collision sensor, a wheel sensor, aspeed sensor, a slope sensor, a weight sensor, a heading sensor, aposition module, a vehicle forward/backward sensor, a battery sensor, afuel sensor, a tire sensor, a steering sensor, a temperature sensor, ahumidity sensor, an ultrasonic sensor, an illumination sensor, a pedalposition sensor, etc. The autonomous driving unit 140 d may implementtechnology for maintaining a lane on which a vehicle is driving,technology for automatically adjusting speed, such as adaptive cruisecontrol, technology for autonomously driving along a determined path,technology for driving by automatically setting a path if a destinationis set, and the like.

For example, the communication unit 110 may receive map data, trafficinformation data, etc. from an external server. The autonomous drivingunit 140 d may generate an autonomous driving path and a driving planfrom the obtained data. The control unit 120 may control the drivingunit 140 a such that the vehicle or the autonomous vehicle 100 may movealong the autonomous driving path according to the driving plan (e.g.,speed/direction control). In the middle of autonomous driving, thecommunication unit 110 may aperiodically/periodically acquire recenttraffic information data from the external server and acquiresurrounding traffic information data from neighboring vehicles. In themiddle of autonomous driving, the sensor unit 140 c may obtain a vehiclestate and/or surrounding environment information. The autonomous drivingunit 140 d may update the autonomous driving path and the driving planbased on the newly obtained data/information. The communication unit 110may transfer information about a vehicle position, the autonomousdriving path, and/or the driving plan to the external server. Theexternal server may predict traffic information data using AItechnology, etc., based on the information collected from vehicles orautonomous vehicles and provide the predicted traffic information datato the vehicles or the autonomous vehicles.

Claims disclosed in the present specification can be combined in variousways. For example, technical features in method claims of the presentspecification can be combined to be implemented or performed in anapparatus, and technical features in apparatus claims of the presentspecification can be combined to be implemented or performed in amethod. Further, technical features in method claims and apparatusclaims of the present specification can be combined to be implemented orperformed in an apparatus. Further, technical features in method claimsand apparatus claims of the present specification can be combined to beimplemented or performed in a method.

1. A method for monitoring a physical downlink control channel (PDCCH)of a user equipment (UE) in a wireless communication system, the methodcomprising: monitoring a PS-PDCCH informing power saving (PS)information in a discontinuous reception-on (DRX-on) duration; andperforming PDCCH monitoring in the DRX-on duration based on the detectedPS-PDCCH, wherein the PS-PDCCH includes information for a specificsearch space set among a plurality of search space sets configured forthe DRX-on duration, and wherein the PDCCH is monitored in search spacesother than the specific search space set among the plurality of searchspace sets.
 2. The method of claim 1, wherein a time interval forskipping the PDCCH monitoring in the specific search space set isinformed or predetermined by a network.
 3. The method of claim 2,wherein in the time interval, monitoring for other PS-PDCCH ismaintained, and wherein the other PS-PDCCH includes informationinforming the UE to wake-up for the specific search space set.
 4. Themethod of claim 1, wherein the PS-PDCCH includes a bitmap informing thespecific search space set.
 5. The method of claim 1, further comprising:receiving a higher layer signal informing a predetermined number ofsearch space sets to which PDCCH monitoring on/off can be applied amongthe plurality of search space sets, wherein the PS-PDCCH includes abitmap informing the specific search space set among the predeterminednumber of search space sets.
 6. The method of claim 5, wherein a numberof bits of the bitmap is determined based on the predetermined number.7. The method of claim 1, wherein the PS-PDCCH further comprises a fieldinforming a wake-up of the UE.
 8. The method of claim 1, wherein atiming of applying PDCCH monitoring based on the PS-PDCCH is determinedto be a same as a minimum applicable delay value applied to a cross-slotscheduling.
 9. The method of claim 1, further comprising: receiving ahigher layer signal informing whether to activate or deactivate PDCCHmonitoring skip in a search space informed by the PS-PDCCH.
 10. Themethod of claim 9, wherein, only when the higher layer signal informsthe activation, PDCCH monitoring can be skipped in the search spaceinformed by the PS-PDCCH.
 11. A user equipment (UE) comprising: atransceiver transmitting and receiving a radio signal; and a processoroperatively coupled with the transceiver, wherein the processor monitorsa PS-PDCCH informing power saving (PS) information in a discontinuousreception-on (DRX-on) duration, and performs PDCCH monitoring in theDRX-on duration based on the detected PS-PDCCH, wherein the PS-PDCCHincludes information for a specific search space set among a pluralityof search space sets configured for the DRX-on duration, and wherein thePDCCH is monitored in search spaces other than the specific search spaceset among the plurality of search space sets.
 12. The UE of claim 11,wherein a time interval for skipping the PDCCH monitoring in thespecific search space set is informed or predetermined by a network. 13.The UE of claim 12, wherein in the time interval, monitoring for otherPS-PDCCH is maintained, and wherein the other PS-PDCCH includesinformation informing the UE to wake-up for the specific search spaceset.
 14. The UE of claim 11, wherein the PS-PDCCH includes a bitmapinforming the specific search space set.
 15. The UE of claim 11, theprocessor receives a higher layer signal informing a predeterminednumber of search space sets to which PDCCH monitoring on/off can beapplied among the plurality of search space sets, wherein the PS-PDCCHincludes a bitmap informing the specific search space set among thepredetermined number of search space sets.
 16. The UE of claim 15,wherein a number of bits of the bitmap is determined based on thepredetermined number.
 17. The UE of claim 11, wherein the PS-PDCCHfurther comprises a field informing a wake-up of the UE.
 18. The UE ofclaim 11, wherein a timing of applying PDCCH monitoring based on thePS-PDCCH is determined to be a same as a minimum applicable delay valueapplied to a cross-slot scheduling.
 19. The UE of claim 11, theprocessor further receives a higher layer signal informing whether toactivate or deactivate PDCCH monitoring skip in a search space informedby the PS-PDCCH. 20-22. (canceled)
 23. An apparatus of a wirelesscommunication system, the apparatus comprising: a processor; and amemory operatively coupled with the processor, wherein the processormonitors a PS-PDCCH informing power saving (PS) information in adiscontinuous reception-on (DRX-on) duration, and performs PDCCHmonitoring in the DRX-on duration based on the detected PS-PDCCH,wherein the PS-PDCCH includes information for a specific search spaceset among a plurality of search space sets configured for the DRX-onduration, and wherein the PDCCH is monitored in search spaces other thanthe specific search space set among the plurality of search space sets.24. (canceled)